I can't believe the only answer here so far hasn't mentioned this and only cared to go into several other supposed plot holes. Yes, JK Rowling did reveal the plothole.

Remember the Squib secretary Ron said he's related to in Book 1? Well, in Rowling's canon, that Squib had a daughter, Mafalda Weasley. In the original Goblet of Fire writing, Mafalda was to spend the summer and her ensuing Hogwarts years with the Weasley clan. It would later be revealed that her parents sent her to the Weasleys because she's just insufferable? Why? How? Simple. Mafalda's role was basically Rita Skeeter. You can see where I'm going now. Mafalda later gets sorted into Slytherin, and she knows a little of everything about everyone.

Oh, she's also Hermione's intellectual equal and this would come as a great annoyance to Hermione as they compete for grades. All these rumors about Harry, his scar, Hagrid, the Harry/Hermione/Krum love triangle, would all come from Mafalda. The insufferable girl. However, she'd also be of some sort of- unspecified help to the trio. She'd be able to help them piece together information, and so on. She was basically a girl who worked solely for herself.

Now, she was ultimately deleted from the book and replaced with Rita Skeeter because of one enormous 'plot hole.' How is it that a little girl can cause so much damage to Harry? Why would the Ministry also take what she says seriously? Not only that, but they'd build on it the next year when arguing that Harry was a dangerous weirdo. How does this one girl manage to spread enough to send Hagrid into his house moping? How does she manage to influence opinion of the entire Wizarding world against Hermione over the letters she got? No- better she gets deleted and replaced. Replaced by Rita Skeeter who has every capability to do what Mafalda was supposed to do because she's a journalist and that's what journalists do.

The Imperius Curse

While often overlooked, the Imperius Curse is, for me at least, the most frightening of all the Unforgivable. Imagine this scenario:

You are walking home from a good day's work at your normal job, just going through your normal routine that you do every day. All of a sudden, you’re overcome by an overwhelming feeling of peace and calmness as a strange voice fills your mind.

Kill your family.

A statement that should fill you with dread is instead greeted with serene tranquility, nothing can affect this strange mood that’s come over you. Perhaps some part of you is screaming that this is not ok but that doesn’t matter. All that matters is this nice serene calmness that is filling your mind. You continue on your journey home, your gait and demeanor unchanged, just as you do every night. You open your front door and are greeted by your lovely wife. You’ve known her since elementary school, you were high school sweethearts and your love for her has never wavered. She’s been with you through thick and thin, as they say, helped you through numerous difficult times.

Kill her.

You watch, with eerie calmness as your hand lifts up to point your wand - when did you unholster your wand? - and point it unshakingly at her smiling face. ‘Avada Kedavra’. Your voice is strangely flat to your ears as if you’re hearing it through cotton wool. Although part of you is screaming in terror, in utter horror, as the love of your life falls dead at your hand, an expression of complete surprise on her face, this unnatural calm that has taken over you remains unchanged. Unfazed. Unaffected. You robotically step over the cooling corpse of your wife and make your way into the kitchen.

Pick up a knife.

Your hand moves without you telling it to, seeking out a sharp knife from a kitchen drawer and grasping it. You continue your steady march into your child's room.

Your child is a year old, a beautiful baby girl. You were so happy when you learned that your wife was pregnant with her. You’d been trying for ages and nothing was working, you’d almost given up hope. Your miracle baby, you often referred to her as. Her bright blue eyes sparkle with happiness, joy, love, and the innocence of youth as you, her loving father, walk closer and closer to her bright white pram.

Slit her throat.

You reach down and pick up your little girl. Somewhere deep down, a distant part of you is screaming NO! but that is unimportant. Everything is unimportant. The voice is all. She giggles as you raise her up, not noticing how your other hand raises, completely outside your own control, bringing the sharp edge of the knife ever closer to her throat.

Blood spurts, squirts of red, blinding as it covers your face. Through the film of red liquid covering your eyes, you watch unfeeling as your little girl's throat opens under the blade, sharp metal cutting through and exposing flesh, trachea, and the flash of white that signifies bone. Her body shudders once as her playful laughter fades away, never to be heard again.

The calmness fades away. The passivity that has suffused your very being since this started leaves as quickly and as unexpectedly as it arrived. You are suddenly very much there, and that’s your daughter's body in your hands, and your wife's dead, and that’s her blood and you did this, you’re a murderer, why couldn’t you stop this, you should have stopped this, oh my god what have you done!!!

The Imperius Curse, ladies and gentlemen. The most fucked up curse ever invented in the Wizarding World.

It must have been a big black hole indeed, because I can still find like fifteen black holes or more.

1- Dumbledore, the “I’m not a bad legilimens myself” wizard, cannot tell the difference between an old friend and an impostor.

2- Paranoid Auror who has the most effective enemy-sensors ever gets captured at home. It seems he doesn’t check his Mirror often enough.

3- The submarine-subterranean ship. Right, a submarine might have worked if Hogwarts was located at Dover and Durmstrang at Trondheim. Or does the ship fly with an overdose of Pixie dust when not underwater?

4- The Goblet. A super-magical object that cannot be fooled or tampered with. Really? After centuries, all that it takes to fool it is a mad wizard? Three is not four.

5- The “no underage pupils allowed.” Dumbledore, the most powerful wizard etc. makes sure no underage pupil can enter the Tournament. Fails. How?

6- Dumbledore himself cannot do anything because of “magic is not might” or something like it… how could Barty?

7- “Are we going to watch an empty lake for hours, Headmaster?”

8- Rosebushes under trees. As if there were not enough rooms in the castle. Even a Room of Requirement.

9- Myrtle in the Prefects’ bathroom. Yeah, she’s dead, but what the hell, dead or alive, stalking is stalking. What about the rest of the ghosts?

10- Fleur, after dealing with a dragon successfully, fails against a creature a fourteen years old has no problems with. Harry has to play the hero, but it’s unbelievable.

11- In spite of the constant stealing of Polyjuice ingredients, the Headmaster suspects nothing. Severus suspects Potter, and not without reason. Those ingredients have to be replaced throughout the year, but no worries. Dumbledore pays the bills.

12- Moody practises the Imperius curse (forbidden) on his pupils. Also, the Cruciatus curse and the Avada Kedavra curse. Thankfully, not on his pupils. Dumbledore? It’s all right, they aren’t that Unforgivable.

13- The charmed Portkey. Gone and back? Why back? Harry should have been dead.

14- Seriously, Dumbledore knows fuck about his best friends.

15- “Are we going to watch a fence for hours, Headmaster?”

16- “Voldemort killed Cedric.” Nope, Peter killed Cedric.

17- Oh wow, Peter was using Voldemort’s wand all the time.

18- “HARRY DIDJA PUT YER NAME IN THE GOBLET OF FIYAH.” Oh well, he didn't, there's foul play but everything's all right.

EDIT: As wossname has kindly pointed out, most of the above don't fit the definition of plot holes; but the author buggered them up all the same.

Perhaps they don't fit the exact definition of black holes either, but bugger it.

Same for JKR’s post-publication explanations. I’ll be buggered if I read them all.

The whole plot was a plot hole.

One word: Quidditch.

Not only is the wizarding world strange enough to have only developed one sport, the single sport that they have makes ZERO sense.

• The scoring system. Score a goal - 10pts. Catch the snitch - 150pts and the game is ended. This is ludicrously unbalanced. 90% of the time the chasers are utterly irrelevant to the outcome of the game. Forget that nonsense going on down below and get me 7 seekers on my team, let's go get that little yellow bitch.
• The crowd. What exactly are they watching? The only thing that matters, catching the snitch, can happen within the stands or a hundred yards out of the stadium! So while I’m watching 6 guys throwing around a quaffle in a finely balanced 40–30, suddenly there's an announcement: “Hey… sorry you couldn't see it… but Potter got the snitch and the game’s finished. Gryffindor win. Have a safe journey home.”

*THE CROWD CAN’T SEE THIS*

• Harry is Gryffindor’s seeker at the age of 11. If I was a fully grown man of 18 and didn't make the team in my senior year because of a child I'd be pissed. Luckily that would never happen, because 11 year olds have only just started flying lessons and that would be ridiculous. Oh, wait.
• Draco becomes a seeker at 12. Seriously, is Hogwarts that bad at producing seekers?!
• Bludgers. “Sorry Mrs McWitchface but your son has unfortunately died during Hufflepuff v Ravenclaw because a 150lb Bludger struck him in the face.” But then Hogwarts never was one for health and safety.

Muggle-borns at Hogwarts must've been like “wtf is this nonsense, let's go watch some football”.

Update 1: Let’s talk about the Quidditch world cup match between Ireland and Bulgaria.

Ireland win 170–160 but Krum catches the snitch. What on earth is a professional sportsman, in a World Cup final, doing knowingly losing his team the game?! Imagine a Super Bowl with Patriots down by 4 with 10 seconds left, it's 4th and goal. What Krum just did was kick the field goal.

The comments saying this game proves chasers are relevant miss the point - the Ireland chasers shouldn't have won the game and only did because Quidditch’s biggest star is an utter moron.

The Bubble-Head Charm.

This is a small one, but it echoes a number of other inconsistencies noted in several other answers.

Harry and Hermione (and Ron too, but mostly just Hermione) spent weeks searching for some kind of magic that would allow Harry to remain under water in the Black Lake for an hour. They searched everywhere they could think of, and they could find nothing helpful.

The day of the challenge, Fleur and Cedric whip out the Bubble-head charm like it was easy. I give them credit for being much more advanced wizards than Harry. Perhaps it was buried in some obscure volume of long-forgotten magic. Or maybe it’s a devilishly tricky little spell that a 4th-year could not hope to conjure…

…until the following year…

In Order of the Phoenix, so many stink-bombs have been let off in the hallways of Hogwarts that students are casting Bubble-head on themselves just to walk between classes. So apparently it’s not that tricky after all.

The plot hole: This seemingly simple, obvious bit of magic eludes Hermione Granger, the brightest witch of her age, a devoted bibliophile, and the most thorough researcher in the school? Not bloody likely. There’s no way Hermione can’t find the Bubble-head charm.

In one phrase, system depiction.

Since the question is not asking for individual plot holes, but weaknesses in general, I've tried to discuss it with a few instances from the books for illustration.

System errors abound throughout the seven books. JKR constructed very elaborate systems for any purpose. She invented a sport, she created a currency, she invented a healthcare system too, in addition to the education system central to the story. But she did not stay consistent to her own rules and constraints. In The Goblet of Fire, the third task clearly happens after the last exam has been written. Yet, there is a mention of having DADA classes free since the real Moody is recuperating. What school has classes after the exams are over? (Some schools in India immediately begin teaching the next year's syllabus before going on summer break but this does not seem to be the case for Hogwarts.) After the first year, they never sing the school song at the start of the year feast again. In The Goblet of Fire, all the students were asked to write the name of their school underneath their own name so that the goblet would be able to pick out one champion per school. If the goblet was tricked into thinking that Harry was competing under a fourth school, why was there no school name on the parchment? The Order of the Phoenix is the first time Harry and the others learn about the grading system. Later, during career counselling, Prof. McGonagall tells him that his Charm work has been E-A. How did he not know the names and the scale of grades before?

As others have written, the math alone could take up pages. Add to that dates (every September 1st is a Monday), the value of money (the Weasleys only have 1 galleon but even a decent quill costs more than 15 sickles), and anything involving numbers in general, and you'll find yourself under an avalanche of inconsistencies which I won't delve into. The whole economy is a mass of contradictions and could never be expected to sustain itself.

Magical education is so unregulated and haphazard. Teachers have near unlimited authority over the students. How is it that Dumbledore allows Snape to terrorize Neville so badly? And no matter how much we all love Hagrid, how does Dumbledore not intervene when he starts bringing dangerous creatures into class? In The Chamber of Secrets, he mentions letters from parents. How is it that these same parents don't say a word when their children are bullied, injured, or otherwise mistreated? On the whole, the wizarding world tolerates a level of physical danger and violence that would leave most Muggles dumbstruck. Some of it may be due to the fact that ordinary injuries are easily mended, but someone taking a tumble down a flight of stairs is merely mentioned in an offhand way, but even wizards could break their spines or suffer brain damage.

Another thing that I don't understand is how young everyone seems to be when they get married and have children. Considering that wizards and witches live for far longer than Muggles, one would expect the exact opposite, since increased life expectancy leads to an extended concept of youth.

I'm reading The Order of the Phoenix right now (yet again) and from a writing point of view, there are times when I'm exasperated both, over plot points that don't hang together when you look at the series as a whole, and tiny details which are mistakes that could simply have been omitted. JKR conveniently writes things that look like cute details that build atmosphere, except that if you think about them, you snap out of the magical world as if you took a Portkey. An example of this is Harry's first detention with Umbridge. Here JKR quite unnecessarily informs us that Umbridge, after having set Harry to writing lines, turned to what looked like a pile of essays to be corrected. It's a small detail, easily overlooked since we are more interested in Harry's plight with the flesh cutting quill. But think about it. This was the only second day of the school year. She had only taught Harry's class on Monday and had not taken any homework from them for correction. Whose essays could she possibly have been correcting? There's wiggle room here, they may not have been essays. She might have taught another class on Monday - but it seems so highly unlikely that she'd have essays to correct the day after school re-opened. JKR could have written anything. Why write something that takes the reader out of the narrative to put that line in a mental courtroom and argue reasonable doubt? All for a pointless piece of detail! She could have said that Umbridge was writing a letter, reading a book, magazine, crocheting another doily - anything. This is something that occurs all too often. Some lines are acquitted on technicalities, like the example above, some, like the math errors aren't.

(Image: Harry Potter et la Magie du Droit - Compte rendu de la conférence )

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Taking an overview, it feels like the first two books differ radically from the rest of the series, which is where many of the inconsistencies lie. JKR transitioned from writing stories meant for children to creating a full blown universe with adult issues and allegories. While she portrayed evolving individual emotions and character relationships brilliantly, she slipped up when it came to system depiction, be it education, economy or life in general. She failed to create a consistent, sustainable universe, but it is her character development skills that make the series is a rich, evocative and endearing part of life.

Pretty much the entirety of Wizarding society.

• Memory modification is accepted as a normal part of society. Moreover, it is required to wipe the memories of muggles in order to preserve the secret.
• But they’re just muggles, so they don’t matter I suppose.
• On that note, muggles have basically no idea what happens to their magical children, and no way to get to Hogwarts to check on them. If you’re unfortunate enough to have a magical child, expect to lose your child completely by the time they’re 25.
• At a minimum, date rape is accepted as a normal occurrence. The story implies we should have sympathy for Merope Gaunt, a woman who regularly date raped a man then was sad that he didn’t want to stay with his rapist. Molly Weasley tells a story about love potions, and Hermione and Ginny both laugh. Romilda Vane uses a love potion and is seemingly unpunished. There is no way to justify any of these other than saying that date rape is acceptable.
• There is no such thing as “cruel or unusual punishments.” I can come up with worse punishments than the dementors, but I would have to get creative… and I’m not sure I could come up with something definitively worse that didn’t invoke magic or futuristic tech in some fashion. In terms of horrific punishments, dementors rank easily in my top 10 for “worst ever.” And they’re a standard punishment for anyone who goes to prison.
• Oh, they’re also acceptable as guards for a school.
• Criminal trials. They should exist. They clearly don’t. Instead there are absurd theatrical performances…. when the Ministry doesn’t just toss someone in prison because they feel like it. (Anyone remember Fudge throwing Hagrid to the dementors because “The Ministry has to be seen to do something”? Not even an apology when they were proven wrong.)
• Squibs are humans. They should be treated as such. This is why I don’t hate Filch… he was miserable, cantankerous, and probably shouldn’t have been around children, but where else could he have gone? The Wizarding World hates squibs, and he’s been treated horribly his entire life. Neville’s family nearly killed him trying to get his magic to show, and nobody cared. At all.
• This also provides a probable explanation for why Dumbledore didn’t care about how Harry was treated at the Dursley’s home. Child abuse may well be common and accepted in the wizarding world.
• The Unbreakable Vow. Sure, this one requires the participants to be willing… but we don’t know if coercion or mind control will work. Worse, age isn’t a factor… the Twins almost swore an Unbreakable Vow with Ron when the latter was only five. And based on how angry Arthur got, it would have worked. Want iron-clad control over your kid? Convince them to swear the vow when they’re too young to understand what it means. Consider a more ruthless version of Lucius who gets Draco to Vow “always to support the Dark Lord Voldemort.” Draco’s life is ruined before he’s old enough to realize what’s happening.
• Polyjuice potion. There is no limit to the ways this could be abused. Sure, it’s not an easy potion to make… but Hermione managed it in her second year. Want an alibi for a crime? Get someone else to polyjuice into you and be somewhere visible when the crime is commited, you use polyjuice to transform into some random muggle (who you obliviate to cover your tracks). Or transform into your worst enemy to frame them. Or into a political rival. Or, as canon demonstrated, transform into a rival or enemy to infiltrate their home and learn their secrets.
• Child welfare. I may personally hate Molly and think she’s overbearing, but if you look at the way the wizarding world acts she kinda has a point. Whether it’s the Ministry stationing soul-sucking demons at Hogwarts or McGonagall sending first-year students to the forbidden forest for a detention, that is a society that just does not seem to care whether its children survive.
• This is somewhat mitigated by their significantly improved medical capacity. Risk assessment looks different when a broken bone is a trivial fix, and even the most mangled of bones can be regrown in a single night. Still, if a forest is bad enough that wizards call it forbidden, it is not appropriate for a detention.

I could keep going, but you get the idea. With only a few very minor tweaks, I would absolutely classify the Harry Potter world as a full-on dystopia.

What I spotted in Order of the Phoenix was something that I don’t think many people realised which is in the very first scene.

If you look at the grass in the background of this shot, you’ll notice that the grass is barren and yellow instead of green. This is something which happens during droughts because there isn't enough rain to feed the grass and is burned by unusually high sunlight levels. Order of the Phoenix is set between 1995–1996. What a lot of people don’t know is that summer of 1995 is statistically the driest summer of all time in the UK and was named as the 1995 drought. There’s also a radio narrator’s voice in the background during the very first shot saying, “I don’t know about you but it’s just too hot out there today isn’t it? And it’s about to get worse, temperatures up in the mid 30s degrees celsius, that’s mid 90s Farenheit, maybe even 100.” It’s a nice touch to throw a bit of history into this scene. It also symbolises Harry being “deserted” from the Wizarding World during this particular summer as nobody is telling him what is going on.

Rowling's world building is imaginative, but she is completely innumerate, and this causes one absurdity after another. For instance...

• Hogwarts is the only wizarding school in Britain, and most wizards and witches attend it. If Harry's year of 40 students is typical, and we generously assume that the average wizard lives 100 years, there are only about 4,000 wizards in Britain. That's a tiny population. I went to a medium-sized university in the UK; those 4,000 wizards would easily fit into their on-campus housing.
• Let's extend that population number a little further. Let's say there are 50 Ministry departments (there are actually more listed on the wiki) with an average of 20 employees each. That would be 1,000 workers. A quarter of the population would work for the Ministry—and the other three-quarters would include not only private-sector workers, but also children, retirees, homemakers, prisoners, the idle rich, etc. (By comparison, Muggle Britain's government employs less than 10% of its population, and Britain's government is not particularly small or efficient.)
• There's a similar absurdity at Ollivanders. If most wizards only buy one wand, that means he sells 40 wands a year. If he sells each for 7 Galleons (the price of Harry's wand), and a Galleon is worth £5, that means he makes £1,400 per year. Frankly, all of the businesses in Diagon Alley and Hogsmeade suffer from this problem—they would not have enough customers to keep the lights on.
• Pivoting away from overall population numbers: Because there's only one teacher per subject, and each year is split into two classes, teachers spend twice as much time in the classroom as students do. I won't run the numbers here because they're long and boring, but in short, either the teachers are tremendously overworked, or the students spend only about a dozen hours per week in a classroom.

The world just doesn't work the way she's written it. There's far too much activity by far too few people.

Some of these probably won’t have been explained at all, but they’re still plot holes that should have been addressed.

The Resurrection Stone: According to Rowling, a horcrux is destroyed when the vessel it is stored in is destroyed beyond repair. This is her explanation as to why, when Harry is bitten by the basilisk in Chamber of Secrets, the horcrux within him is not destroyed…because Harry was healed by Fawkes and therefore not destroyed beyond repair, i.e. killed. So why, then, does the Resurrection Stone still work as its intended function after Dumbledore destroys it?

Rowling came out with the hackneyed explanation that only Dumbledore could have extracted the soul without damaging the Stone…wut. The explicit instruction for destroying a horcrux is to destroy it beyond repair!

But then, if Dumbledore was so aware that what he had in his hands was in fact the Resurrection Stone, then don’t you think he would have been prepared for the inevitable curse that Voldemort would have placed upon it?

The Elder Wand: I understand the whole rigmarole around wand-lore and how some wands are more powerful than others because of the inherent magical power of the creature that provided the core and how there’s different types of wood that carry different properties and how they’re semi-sentient and choose the wizard and how wand-allegiance is somehow a thing no one talks about but is suddenly a very important part of the Wizarding World and using multiple wands is like a level-up boost but for some reason no one ever uses this trick…inhale. I get it. It’s one of those things that has so much to it, like economics or governing bodies that a writer will never get every detail into the book without boring the reader to death.

However, there’s the issue of the Elder Wand’s allegiance to Harry. Okay, so Dumbledore is magically disarmed by Draco, therefore making him the master of the Elder Wand. Fine. Then, Harry physically wrestles Draco’s wand, not the Elder Wand mind you, but a normal wand out of Draco’s hand, and suddenly the Elder Wand belongs to Harry? I don’t buy it. According to Rowling, the owner of the wand has to be aware they are the owner, and really not want to lose it, in order to be considered ‘conquered’. Draco has no idea the Elder Wand belongs to him, and therefore cannot fear losing it. He can fear losing his own wand, which he does, which is why its allegiance changes to Harry. Fair enough.

When Harry wrestles Draco’s “everyday” wand out of his hand at the Malfoy’s mansion, he conquers Draco, and therefore the Elder Wand — hidden in Dumbledore’s tomb at the time — transfers its allegiance to Harry.

…

“But, no, I really wanted, very consciously, for the history of the wizarding world to hinge on this moment where two teenage boys have a physical [fight]. They don’t even do it by magic,” Rowling said.

Today’s Confused by Potter? Author sets record straight by Jen Brown

I feel like the Elder Wand’s allegiance would have been in limbo, owned by Draco, but not acknowledged. It would have to take another conquering in order to fully shift the allegiance, as in, the way Harry conquers Voldemort whilst Voldemort is using the Elder Wand…then its allegiance would have shifted. From Draco to Harry, it still wouldn’t have been Voldemort’s. From what we’ve seen of wands, people can use other people’s wands just fine without causing loyalty confusion, so technically Voldemort would have been ‘borrowing’ Draco’s wand, and there would be no issue because again, Draco has no idea it belongs to him, so no jealousy or uncertainty would ensue.

The Cloak of Invisibility: Apparently I have an issue with the Deathly Hallows. So the Cloak. It’s awesome. It’s useful. It’s one hell of a fashion accessory. It repels spells. It doesn’t fray and doesn’t need washing. So, what’s the plot hole? Dumbledore can see people under it? And so can cats. All right, I’ll give you cats. My cats see invisible things all the time, I won’t question it. But Rowling’s explanation of why Dumbledore can see through it just make my eyes twitch.

J.K. Rowling: Dumbledore, who could perform magic without needing to say the incantation aloud, was using ‘homenum revelio’ - the human-presence-revealing spell Hermione makes use of in Deathly Hallows.

So you’re telling me that Dumbledore is so paranoid that every time he enters a room or at steady intervals of time whilst in a room, he just randomly casts homenum revelio just to make sure he’s not being watched. How many invisibility cloaks does he think exist? Or does he just think Harry is stalking him? Is it a reflex, like doing kegels? If this is the case, why wouldn’t he have detected Voldemort hanging out on the back of Quirrel’s head?

Harry’s Crime of Performing Magic in Front of Muggles: Within the Wizarding laws, there’s a provision for muggles who have children or siblings that are magical. They are obviously aware that the magical world exists, and underage witches and wizards can’t control their magic, so it comes out of them at unexpected times, and parents are expected to do what they can to control their magical offspring. That’s well established. So why, when Harry performs the Patronus Charm in front of his cousin that he grew up with, does he get in trouble for performing magic in front of a muggle? Dudley is well aware the magical world exists. He’s seen magic. He’s been the victim of many a magical spell. Arthur Weasley performs plenty of magic in front of the Dursleys. Why is none of that persecuted? (Not that I’m sympathetic, the Dursleys got what they deserved.)

Obviously there’s the bias of the Ministry at the time to discredit Harry, but still. Laws are laws.

Hagrid’s Tiny Father: This one is just weird to me. So Hagrid explains that his father was so small that at the age of 11, he could pick him up in one hand and set him up on the dresser. Hagrid isn’t that big. So how small was this dude? Was he a dwarf? And he had successful coitus with a full-on giant. Whaaaaat? Did he crawl inside and give himself a handy? How does this work? Gross images now flooding my head. Even if he were average sized, that sort of hankypanky would be extremely difficult.

Trolls in the dungeon will cause comments to be blocked. Unless you’re a Slytherin, then it’s expected.

There are no major plot hole in OotP. If the Book is so massive (the first french version was more than a 1000 pages), it's because a lot of the Wizarding World Mythologie is exposed in that book. There is a very accurate description of the ministry of Magic. They put in place the Order of the Phoenix and what it does. New characters like Luna and Tonks are introduced.

Also there are a lot of things going on. OotP is a very political book. Political in the sense that we dive in the politics of the ministry and a power struggle between Fudge and Dumbledore, with each of them having some interests to défend. Fudge wants to keep his job as Minister and Dumbledore wants the Wizarding World to know Voldemort is back. And those things don't align. Fudge believes Dumbledore wants to use the threat of Voldemort to take his job and so he makes his moves. Dumbledore (and Harry) makes his moves to protect the Wizarding World.

Finally, we have a lot of character growth in that book. Yes, Harry is whining all the time but he is 15. So he should get a pass just for that. Then on top of puberty, there is also the fact that he is having some PTSD. The previous year, Harry got thrown in the whole Triwizard tournament and at the end he and Cedric got kidnapped, Cedric was killed, Harry was tortured and he narrowly escaped it.

That's quite a lot to go throught.

So no plot hole. But a lot of plots.

Thanks for the A2A. I will try to answer it in the best possible way that I can.

Magic is littered throughout the HP books and movies. But some of the small things that I noticed were.

#1

In 'Order of the Phoenix,' there's a Wizarding World version of Cheerios called Cheeri-Owls.

If you look closely during one breakfast scene in "The Order of the Phoenix," you can clearly see a Wizarding World version of the breakfast cereal Cheerios.

In the Harry Potter universe, however, they're called Cheeri-Owls — much more exciting than our muggle version.

#2

The end credits of 'Goblet of Fire' feature this magical disclaimer: 'No dragons were harmed in the making of this movie.'

Baby Norbert the dragon was featured in "The Sorcerer's Stone" as the pet Hagrid had to give up, but it wasn't until "The Goblet of Fire" that we saw fully grown dragons as part of the Triwizard Tournament.

While every film features an end credits "no animals were harmed in the making of this movie" disclaimer, the makers clearly felt the needed to ensure audiences knew magical creatures were safe, too.

#3

The Ministry of Magic's access code is 6-2-4-4-2, which spells out m-a-g-i-c.

When Harry is summoned to the Ministry of Magic in "The Order of the Phoenix" for using magic outside school (he warded off a couple of dementors with a patronus charm), he is escorted by Arthur Weasley.

Arthur takes Harry into a phone box, wherein he dials a number, and the phone box descends below into the Ministry. It's a neat little trick, but the number Arthur dials is 6-2-4-4-2, which spells out m-a-g-i-c on telephone dials. This is probably not the most secure password for the Ministry of Magic to have, but is a nice detail for the filmmakers to include.

#4

In 'Goblet of Fire,' we catch a shot of the Deathly Hallows symbol way before we even knew what they were.

Eagle-eyed viewers spotted this symbol of the deathly hallows way back in "The Goblet of Fire," a full three movies before we were introduced to them.

The deathly-hallows symbol is a triangle (representing the invisibility cloak), with a line running through the center (representing the elder wand), with a circle inside (representing the resurrection stone). You can see these symbols in the glass cabinet Dumbledore is looking into here.

#5

Slughorn drinks a vial of liquid luck right before the Battle of Hogwarts in 'Deathly Hallows — Part II.'

Right before the Battle of Hogwarts, just before Slughorn, McGonagall, Mrs. Weasley, and the rest cast a protective shield around the castle, he drinks a vial of felix felicis — aka liquid luck.

This is a nifty idea from Slughorn, and he ended up surviving the battle, so it clearly worked. His drinking of that potion could even be the reason the good guys won.

#6

In 'Deathly Hallows — Part II,' Harry, Ron, and Hermione fight giant spiders, a troll, dementors, and a werewolf — all enemies they fought in the first three movies.

"The Deathly Hallows — Part II" concludes the "Potter" saga pretty perfectly, and it does so by flashing back to the first few entries in ways you may not notice at first.

In the climactic Battle of Hogwarts, Harry, Ron, Hermione, and co. fight off trolls, acromantula (giant spiders), a werewolf (Fenrir Greyback), and dementors. These are all enemies they fought in the first three movies.

In "The Sorcerer's Stone," Harry and Ron saved Hermione from a cave troll in the girl's bathroom; in "The Chamber of Secrets," Harry and Ron fought off Aragog and his colony of acromantula; and in "The Prisoner of Azkaban," the trio faced a werewolf (Remus Lupin) and a horde of dementors.

#7

In 'The Sorcerer's Stone,' you can see Aunt Petunia dying Dudley's old clothes gray for Harry's school uniform, which was a scene in the books.

In the books, there's a scene in which Aunt Petunia dyes her son Dudley's old clothes gray so Harry can wear them as his school uniform. The clothes are huge on him, and this is one of many things the Dursleys do that shows their vile treatment toward Harry.

This detail, however, is never mentioned explicitly in the films, but you can see Aunt Petunia dying the clothes in the background of "The Sorcerer's Stone."

#8

The Leaky Cauldron sign is only visible to magic folk.

The sign to the Leaky Cauldron is black and blank at first, but as Hagrid and Harry approach it, it slowly fills itself in and displays a black and gold emblem with a cauldron on it reading "The Leaky Cauldron."

As we know, muggles can't see magic, so this suggests that the sign lights up only because Hagrid and Harry, magical folk, are approaching it. So if you see any blank signs outside buildings in London, you can probably assume it's a wizards' pub.

Just joking. But it’s great that movies put this in.

So these were the small details that I noticed. Please do tell me your noticings in the comment section.

Signing off 🖋

A fellow Potterhead ⚡️

Diya 💜

The fact that a powerful r*pe drug is sold to minors without any law enforcement or parent ever batting an eye. I’m talking about Amortentia

Students need a parental consent to go on brief weekend trips to a nearby town. Ok, seems reasonable.

What is completely nonsensical is that a school is able to house a literal hellhound

Soul-sucking abominations

A convicted murderer and torturer

Either without noticing, without asking consent from the parents or the school board or without anyone raising even the slightest complaint.

Did JK Rowling write Harry Potter and the Goblet of Fire? The style is very different from books 1-3.

Really? 🙄

Yes! JK Rowling wrote Goblet of Fire. Nobody disputes that.

The narration style in GoF is not so different from books 1–3 that it reads like a different author, but it does show a progression.

At the beginning of the series, Harry is 11, and at the end of the series Harry is 17. JK Rowling’s narration style gradually shifts from a British Kid Lit style to a British YA style to mirror the gradual aging up of her characters.

But other than some tonal shifts, and moderately more advanced vocabulary and sentence structures, JKR’s writing style is unmistakably hers (though it does follow British Kid Lit conventions) and is fundamentally the same throughout the series.

A look at the first few paragraphs from some of the books will give you an idea of how JKR’s narration style evolved.

PS ch 1:

Mr. and Mrs. Dursley, of number four, Privet Drive, were proud to say that they were perfectly normal, thank you very much. They were the last people you'd expect to be involved in anything strange or mysterious, because they just didn't hold with such nonsense.

Mr. Dursley was the director of a firm called Grunnings, which made drills. He was a big, beefy man with hardly any neck, although he did have a very large mustache. Mrs. Dursley was thin and blonde and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over garden fences, spying on the neighbors. The Dursleys had a small son called Dudley and in their opinion there was no finer boy anywhere.

The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters. Mrs. Potter was Mrs. Dursley's sister, but they hadn't met for several years; in fact, Mrs. Dursley pretended she didn't have a sister, because her sister and her good-for-nothing husband were as unDursleyish as it was possible to be. The Dursleys shuddered to think what the neighbors would say if the Potters arrived in the street. The Dursleys knew that the Potters had a small son, too, but they had never even seen him. This boy was another good reason for keeping the Potters away; they didn't want Dudley mixing with a child like that.

The narration is clearly aimed at children, and evokes a style which is common to British Kid Lit. Take the opening of The Hobbit, by JRR Tolkien, for example:

TH ch 1:

In a hole in the ground there lived a hobbit. Not a nasty, dirty, wet hole, filled with the ends of worms and an oozy smell, nor yet a dry, bare, sandy hole with nothing in it to sit down on or to eat: it was a hobbit-hole, and that means comfort.

It had a perfectly round door like a porthole, painted green, with a shiny yellow brass knob in the exact middle. The door opened on to a tube-shaped hall like a tunnel: a very comfortable tunnel without smoke, with panelled walls, and floors tiled and carpeted, provided with polished chairs, and lots and lots of pegs for hats and coats-the hobbit was fond of visitors. The tunnel wound on and on, going fairly but not quite straight into the side of the hill-The Hill, as all the people for many miles round called it-and many little round doors opened out of it, first on one side and then on another. No going upstairs for the hobbit: bedrooms, bathrooms, cellars, pantries (lots of these), wardrobes (he had whole rooms devoted to clothes), kitchens, dining-rooms, all were on the same floor, and indeed on the same passage. The best rooms were all on the left-hand side (going in), for these were the only ones to have windows, deep-set round windows looking over his garden, and meadows beyond, sloping down to the river.

This hobbit was a very well-to-do hobbit, and his name was Baggins. The Bagginses had lived in the neighbourhood of The Hill for time out of mind, and people considered them very respectable, not only because most of them were rich, but also because they never had any adventures or did anything unexpected: you could tell what a Baggins would say on any question without the bother of asking him. This is a story of how a Baggins had an adventure, and found himself doing and saying things altogether unexpected. He may have lost the neighbours' respect, but he gained-well, you will see whether he gained anything in the end.

And here is a sample of James and the Giant Peach by Roald Dahl:

JatGP ch 1:

Until he was four years old, James Henry Trotter had a happy life. He lived peacefully with his mother and father in a beautiful house beside the sea. There were always plenty of other children for him to play with, and there was the sandy beach for him to run about on, and the ocean to paddle in. It was the perfect life for a small boy.

Then, one day, James's mother and father went to London to do some shopping, and there a terrible thing happened. Both of them suddenly got eaten up (in full daylight, mind you, and on a crowded street) by an enormous angry rhinoceros which had escaped from the London Zoo.

Now this, as you can well imagine, was a rather nasty experience for two such gentle parents. But in the long run it was far nastier for James than it was for them. Their troubles were all over in a jiffy. They were dead and gone in thirty-five seconds flat. Poor James, on the other hand, was still very much alive, and all at once he found himself alone and frightened in a vast unfriendly world. The lovely house by the seaside had to be sold immediately, and the little boy, carrying nothing but a small suitcase containing a pair of pyjamas and a toothbrush, was sent away to live with his two aunts.

Their names were Aunt Sponge and Aunt Spiker, and I am sorry to say that they were both really horrible people. They were selfish and lazy and cruel, and right from the beginning they started beating poor James for almost no reason at all. They never called him by his real name, but always referred to him as 'you disgusting little beast' or 'you filthy nuisance' or 'you miserable creature', and they certainly never gave him any toys to play with or any picture books to look at. His room was as bare as a prison cell.

The narrator in each of the cases is telling a story in a lighthearted manner which appeals to children (and many adults). The vocabulary and sentence structure is basic, and easy to understand, and there is a distinctively British “accent” (Tolkien’s sentence structures are a bit more complex, admittedly, but they are balanced in a manner which achieves the same effect).

For all intents and purposes, the Narrator is a character in and of themselves (this is a Kid Lit literary convention, a convention which Lemony Snickett’s a Series of Unfortunate Events satirises to great comic effect).

That was JK Rowling’s starting point.

In Chamber of Secrets, you can already see a slight shift:

CoS ch 1:

Not for the first time, an argument had broken out over breakfast at number four, Privet Drive. Mr. Vernon Dursley had been woken in the early hours of the morning by a loud, hooting noise from his nephew Harry's room.

"Third time this week!" he roared across the table. "If you can't control that owl, it'll have to go!"

Harry tried, yet again, to explain.

"She's bored ," he said. "She's used to flying around outside. If I could just let her out at night--"

"Do I look stupid?" snarled Uncle Vernon, a bit of fried egg dangling from his bushy mustache. "I know what'll happen if that owl's let out."

He exchanged dark looks with his wife, Petunia.

"WHAT HAVE I TOLD YOU," thundered his uncle, spraying spit over the table, "ABOUT SAYING THE M'WORD IN OUR HOUSE?"

"But I--"

"HOW DARE YOU THREATEN DUDLEY!" roared Uncle Vernon, pounding the table with his fist.

"I just--"

"I WARNED YOU! I WILL NOT TOLERATE MENTION OF YOUR ABNORMALITY UNDER THIS ROOF!"

Harry stared from his purple-faced uncle to his pale aunt, who was trying to heave Dudley to his feet.

"All right," said Harry, " all right..."

Uncle Vernon sat back down, breathing like a winded rhinoceros and watching Harry closely out of the corners of his small, sharp eyes.

Ever since Harry had come home for the summer holidays, Uncle Vernon had been treating him like a bomb that might go off at any moment, because Harry Potter wasn't a normal boy. As a matter of fact, he was as not normal as it is possible to be.

Harry Potter was a wizard - a wizard fresh from his first year at Hogwarts School of Witchcraft and Wizardry. And if the Dursleys were unhappy to have him back for the holidays, it was nothing to how Harry felt.

He missed Hogwarts so much it was like having a constant stomachache. He missed the castle, with its secret passageways and ghosts, his classes (though perhaps not Snape, the Potions master), the mail arriving by owl, eating banquets in the Great Hall, sleeping in his four-poster bed in the tower dormitory, visiting the gamekeeper, Hagrid, in his cabin next to the Forbidden Forest in the grounds, and, especially, Quidditch, the most popular sport in the wizarding world (six tall goal posts, four flying balls, and fourteen players on broomsticks).

The narrative structure is a bit different; it begins with a character driven scene because there is a presumption that most people have read the first book. It isn’t until we get to the “recap” paragraphs, that we can more obviously see the difference.

There is still a sense that the Narrator is telling a story to children, due to the vocabulary, but the more whimsical styling of the first book is lesser in the second. It’s a bit more straightforward and clearly aimed at slightly older children.

Then we move on to Prisoner of Azkaban:

PoA ch 1:

Harry Potter was a highly unusual boy in many ways. For one thing, he hated the summer holidays more than any other time of year. For another, he really wanted to do his homework but was forced to do it in secret, in the dead of night. And he also happened to be a wizard.

It was nearly midnight, and he was lying on his stomach in bed, the blankets drawn right over his head like a tent, a flashlight in one hand and a large leather-bound book (A History of Magic by Bathilda Bagshot) propped open against the pillow. Harry moved the tip of his eagle-feather quill down the page, frowning as he looked for something that would help him write his essay, 'Witch Burning in the Fourteenth Century Was Completely Pointless -- discuss.'

The quill paused at the top of a likely looking paragraph. Harry pushed his round glasses up the bridge of his nose, moved his flashlight closer to the book, and read:

Non-magic people (more commonly known as Muggles) were particularly afraid of magic in medieval times, but not very good at recognizing it. On the rare occasion that they did catch a real witch or wizard, burning had no effect whatsoever. The witch or wizard would perform a basic Flame-Freezing Charm and then pretend to shriek with pain while enjoying a gentle, tickling sensation. Indeed, Wendelin the Weird enjoyed being burned so much that she allowed herself to be caught no less than forty-seven times in various disguises.

Harry put his quill between his teeth and reached underneath his pillow for his inkbottle and a roll of parchment. Slowly and very carefully he unscrewed the ink bottle, dipped his quill into it, and began to write, pausing every now and then to listen, because if any of the Dursleys heard the scratching of his quill on their way to the bathroom, he'd probably find himself locked in the cupboard under the stairs for the rest of the summer.

The Dursley family of Number Four, Privet Drive, was the reason that Harry never enjoyed his summer holidays. Uncle Vernon, Aunt Petunia, and their son, Dudley, were Harry's only living relatives. They were Muggles, and they had a very medieval attitude toward magic. Harry's dead parents, who had been a witch and wizard themselves, were never mentioned under the Dursleys' roof. For years, Aunt Petunia and Uncle Vernon had hoped that if they kept Harry as downtrodden as possible, they would be able to squash the magic out of him. To their fury, they had not been unsuccessful. These days they lived in terror of anyone finding out that Harry had spent most of the last two years at Hogwarts School of Witchcraft and Wizardry. The most they could do, however, was to lock away Harry's spell books, wand, cauldron, and broomstick at the start of the summer break, and forbid him to talk to the neighbors.

The very first paragraph of that chapter is a narrative callback to the childlike whimsy of the first book, but the rest of the scene is decidedly more grown up. The whimsy is much less childlike and more satirical in tone.

Goblet of Fire opens with a chapter which nearly dispenses with the childlike whimsy—but not quite. The tone is much more adult, but the satirical elements still give a nod and a wink to the childlike whimsy, and it’s still obviously a story told by the same Narrator, and written by the same writer:

GoF ch 1:

The villagers of Little Hangleton still called it "the Riddle House," even though it had been many years since the Riddle family had lived there. It stood on a hill overlooking the village, some of its windows boarded, tiles missing from its roof, and ivy spreading unchecked over its face. Once a fine-looking manor, and easily the largest and grandest building for miles around, the Riddle House was now damp, derelict, and unoccupied.

The Little Hangletons all agreed that the old house was "creepy." Half a century ago, something strange and horrible had happened there, something that the older inhabitants of the village still liked to discuss when topics for gossip were scarce. The story had been picked over so many times, and had been embroidered in so many places, that nobody was quite sure what the truth was anymore. Every version of the tale, however, started in the same place: Fifty years before, at daybreak on a fine summer's morning when the Riddle House had still been well kept and impressive, a maid had entered the drawing room to find all three Riddles dead.

The maid had run screaming down the hill into the village and roused as many people as she could.

"Lying there with their eyes wide open! Cold as ice! Still in their dinner things!"

The police were summoned, and the whole of Little Hangleton had seethed with shocked curiosity and ill-disguised excitement. Nobody wasted their breath pretending to feel very sad about the Riddles, for they had been most unpopular. Elderly Mr. and Mrs. Riddle had been rich, snobbish, and rude, and their grown-up son, Tom, had been, if anything, worse. All the villagers cared about was the identity of their murderer - for plainly, three apparently healthy people did not all drop dead of natural causes on the same night.

The Hanged Man, the village pub, did a roaring trade that night; the whole village seemed to have turned out to discuss the murders. They were rewarded for leaving their firesides when the Riddles' cook arrived dramatically in their midst and announced to the suddenly silent pub that a man called Frank Bryce had just been arrested.

Though the childishness is gone, some of the descriptive vocabulary, “strange and horrible”, and phrasing such as, “…for plainly, three apparently healthy people did not all drop dead of natural causes on the same night,” recalls the whimsical narration style of Philosopher’s Stone.

The gradual progression couldn’t be more clear.

It’s more adult, sure, and if you read GoF immediately after reading PS, it might seem like a leap. But if you read the books in order, you can see that the more adult structure of GoF doesn’t sacrifice the underlying style. There is a satirical throughline which ties all of the books together stylistically.

You can still see it in Order of the Phoenix:

OotP ch 1:

The hottest day of the summer so far was drawing to a close and a drowsy silence lay over the large, square houses of Privet Drive. Cars that were usually gleaming stood dusty in their drives and lawns that were once emerald green lay parched and yellowing--for the use of hosepipes had been banned due to drought. Deprived of their usual car-washing and lawn-mowing pursuits, the inhabitants of Privet Drive had retreated into the shade of their cool houses, windows thrown wide in the hope of tempting in a nonexistent breeze. The only person left outdoors was a teenage boy who was lying flat on his back in a flowerbed outside number four.

He was a skinny, black-haired, bespectacled boy who had the pinched, slightly unhealthy look of someone who has grown a lot in a short space of time. His jeans were torn and dirty, his T-shirt baggy and faded, and the soles of his trainers were peeling away from the uppers. Harry Potter's appearance did not endear him to the neighbours, who were the sort of people who thought scruffiness ought to be punishable by law, but as he had hidden himself behind a large hydrangea bush this evening he was quite invisible to passers-by. In fact, the only way he would be spotted was if his Uncle Vernon or Aunt Petunia stuck their heads out of the living-room window and looked straight down into the flowerbed below.

On the whole, Harry thought he was to be congratulated on his idea of hiding here. He was not, perhaps, very comfortable lying on the hot, hard earth but, on the other hand, nobody was glaring at him, grinding their teeth so loudly that he could not hear the news, or shooting nasty questions at him, as had happened every time he had tried sitting down in the living room to watch television with his aunt and uncle.

Almost as though this thought had fluttered through the open window, Vernon Dursley, Harry's uncle, suddenly spoke.

'Glad to see the boy's stopped trying to butt in. Where is he, anyway?'

'I don't know,' said Aunt Petunia, unconcerned. 'Not in the house.'

As a whole, the descriptions are more detailed, and the tone more adult, but satirical sentences like, “Harry Potter's appearance did not endear him to the neighbours, who were the sort of people who thought scruffiness ought to be punishable by law,” continue to maintain a slight element of whimsy and carry it through to the end of Deathly Hallows.

That was one of JK Rowling’s more ingenious strokes which, along with highly relatable characters and largely well-written dialogue (with a few minor hiccups), elevates the Harry Potter series above most children’s or YA fantasy series.

For all of its many, many flaws, the Harry Potter series is still a work of genius that few authors can match.

JK Rowling isn’t Shakespeare, but she is unqestionably an above average writer when she’s on her game.

The HP fandom community would not be so massive, and the internecine battles between Team Snape and Team Harry, and the battles between Team Romione and Team Harmony, would not be so intense if the books and characters weren’t as well-written and engaging as they are.

MANDRAKES! and the fact that Professor Sprout raises these humanoids from infancy to adulthood, at which point she slaughters the sentient Mandrakes to create the Restorative Draught. Dark and MAJORLY ignored.

Astute readers will note that Rowling intentionally humanizes the Mandrakes. This is less apparent in the movies.

The mandrakes have humanoid physiology, humanoid developmental patterns, humanoid conversations with Professor Sprout, and humanoid social growth patterns.

As humans are the only known species to have an extended puberty and develop acne thence, this is mildly horrifying:

The moment their acne clears up … it won’t be long until we’re cutting them up and stewing them. You’ll have Mrs. Norris back in no time.

CoS Chapter 6:

Instead of roots, a small, muddy, and extremely ugly baby popped out of the earth. The leaves were growing right out of his head. He had pale green, mottled skin, and was clearly bawling at the top of his lungs.

Note the use of the male pronoun. Given that the series is GENERALLY told from Harry’s perspective, there’s only one way he was able to determine its sex … Think of the implications this has for the Mandrake’s reproductive habits. They also throw parties and move into their partner’s pot … This is no normal plant. Also note the baby human-like response to being uncomfortable.

CoS Chapter 9:

Mandrakes didn’t like coming out of the earth, but didn’t seem to want to go back into it either. They squirmed, kicked, flailed their sharp little fists, and gnashed their teeth[.]

Once again, they exhibit resistance, human-like emotions, and sentience.

CoS Chapter 11:

[It] was so important for the Mandrakes to grow quickly and revive Mrs. Norris and Colin Creevey.

They are being raised like pigs for slaughter.

CoS Chapter 13:

Madam Pomfrey was pleased to report that the Mandrakes were becoming moody and secretive, meaning that they were fast leaving childhood. “The moment their acne clears up, they’ll be ready for repotting again ... after that, it won’t be long until we’re cutting them up and stewing them. You’ll have Mrs. Norris back in no time.”

Moody and secretive?! Leaving childhood?! Acne?! Cutting them up and stewing them?! This is horrific. As mentioned before, humans are the only species to endure an extended puberty. This isn’t simple anthropomorphism, Rowling is intentionally humanizing the Mandrakes.

CoS Chapter 14:

[In] March several of the Mandrakes threw a loud and raucous party in greenhouse three. This made Professor Sprout very happy. “The moment they start trying to move into each other’s pots, we’ll know they’re fully mature,” she told Harry. “Then we’ll be able to revive those poor people in the hospital wing.”

While Professor Sprout was presumably “very happy” that she would be able to revive the petrified / potentially stop the Heir of Slytherin attacks, it’s extremely dark to imagine her watching, raising, and interacting with these teenagers / young adults and anticipating butchering them.

Suspending disbelief, I’m fully aware that (1) these are plants and (2) people (myself included) eat meat and allow the slaughter of animals for survival. The question asks about dark elements in the series that are ignored—the nonchalant raising and slaughtering of humanoids is indeed dark and ignored.

Justin Finch-Fletchley. He was admitted to Eton but he convinced his parents to allow him to attend Hogwarts. This would be like Bill Gates dropping off the map at age eleven. His parents have friends. What crazy cover story do they give out? After all, Justin shows up on Yule holidays and over the summer. The only option is that Justin is attending some weird school in Switzerland that no one has heard off. Or whatever. Harry is easy to explain. He’s attending a school for the Almost Criminally Insane or something. He’s been off the map a lot. He has no friends in Little Wingding. Apparently Hermione doesn’t have any friends either and her parents are some sort of weird reclusive types. It’s not an environment where the Vicar says “Where’s Hermione?” Just don’t seem to be any of the normal social connections where a neighbor notices Hermione has an owl that flies in and out of her room.

And then the British government knows about the Wizarding population but it doesn’t leak out. The U.K. government would be right to consider the magic folk a potential threat and to establish an agency to keep track of wizard activity.

Lots and lots of plot holes, but I think she would have corrected the time-turner paradox.

Yes, it is the whole plot of Prisoner of Azkaban, and it would be hard to imagine the plot without it, but it cascaded into a lot of time-travel paradoxes and inconsistencies. In fact, J.K. Rowling herself realized the problems it caused and decided on destroying all the time-turners in Order of the Phoenix. Maybe if she didn’t introduce at all in her series we wouldn’t have had to suffer the Cursed Child abomination.

I very badly DON’T want her to do that.

She did very well with those novels. Most of the “inconsistencies” are not so inconsistent to people who actually pay attention to only the first 7 books(none of that cursed child nonsense)

And nearly everything she has added to it since is … well… awful.

I love the history part of her additions but not much else.

Shes a classic case of someone who needs to learn to leave well enough alone.

If she went back and rewrote them or, worse yet, wrote prequels to explain crap… i feel like that would put her in league with George Lucas.. a man who had awesomeness… and very nearly killed it for everyone.

Please, please, PLEASE dont let JK Rowling do this. EvER.

What is something really dark in the Harry Potter story that nearly everyone overlooks?

That James and Lily Potter encourage their own son to go to his death.

Lily’s smile was widest of all. …her green eyes, so like his (Harry’s), searched his face hungrily...

“You’ve been so brave.”

He (Harry) could not speak…

“You are nearly there,” said James. “Very close. We are ... so proud of you.”

“Does it hurt?”

“Dying? Not at all,” said Sirius (Black). “Quicker and easier than falling asleep.”

“And he will want to be quick. He wants it over,” said (Remus) Lupin.

Harry Potter and the Deathly Hallows — J.K. Rowling

Most people defend this scene by claiming James and Lily “knew” Harry was going to live. Others say James and Lily didn’t actually “encourage” Harry.

But it’s still a matter of two parents letting their child believe he was going to die, which, I’m sorry, but that’s as disturbing as it gets, no matter how anyone tries to sugarcoat it.

It’s just not what anyone with an ounce of sanity would call “good parenting.”

I mean, what are we to believe? That Albus Dumbledore got together with Lily and James beyond the grave and said, “Look, I know… that you know… that Harry’s going to make it out alive… but he really needs to believe he’s going to die, so, can you just kind of play along?”

And the same goes for Sirius Black and Remus Lupin, while we’re on the subject.

Sirius basically says, “No big deal, Harry! It’s like catching some zzzz’s!” But Sirius was always off his rocker anyway, so while that’s certainly dark, it’s also not surprising coming from Mr. Padfoot.

Someone in another answer (or maybe it was a comment) suggested that this is what makes the Resurrection Stone a piece of Dark Magic, because maybe that wasn’t really James and Lily Potter who were talking to Harry (yikes, I just got a shiver thinking about that) meaning the stone is basically a harbinger of evil to anyone who possesses it.

That actually makes a lot of sense, considering Albus Dumbledore immediately succumbed to it when he put on Gaunt’s Ring and terminally cursed himself, and it basically took a miracle for Harry not to die.

But that scene in the Forbidden Forest, when James and Lily appear so pleased that Harry’s going to join them shortly… that’s not just a little bit horrifying, I don’t care how many people love Albus Dumbledore and think he had it all planned out perfectly.

It’s not completely unlike that scene at the end of The Exorcist, when Father Karras hears the demon speaking to him in his dead mother’s voice, forcing Karras to leap out the window to his suicide, taking the demon with him.

It is quite spine-tingling to think about James and Lily just kind of standing there, all smiles while Harry gets ready to walk to what he thinks is his own death.

Hermione's parents.

At the beginning of the Deathly Hallows, Hermione casually mentions to Ron and Harry that she altered her parents' memories and gave them new identities as Wendell and Monica Wilkins who wish to move to Australia, to protect them from the Death Eaters.

Imagine for a second, doing that to your parents, whom you have known all your life, who you know loves you more than anyone else in the entire world. If something goes wrong, then Hermione is left parentless.

Hermione made the biggest sacrifice of them all, but no one even bothered to check how she was doing with it throughout the entire period. She left her parents in such a state to fight along with Ron and Harry.

That takes guts and a huge amount of bravery. For a child to do that to their own parents for whatever reason, is extraordinary I think.

But sadly, it is just ignored in the book and the movie. A mere bump on the road in the whole scheme of things.

As Jacob Erickson said in his response, it's a plot hole. In fact, part of the book has characters acting inconsistently.

• There is no logical reason why Harry did not open Sirius' gift. He could have seen him before he judged him to be dangerous for Sirius.
• There is no reason why Voldemort should not go and seek the prophecy himself. In the seventh book, he is able to become invisible with a simple spell.
• There's no reason Hermione can't protect the DA's list of names with a tongue block spell or the Fidelius Charm.
• There is no reason why Dumbledore didn't explain to Harry that he should keep his distance from him until he (Harry) learned about Oclumency, because Voldemort could see through his eyes.
• Etc.

However, the lack of security can be explained by the fact that no one thought anyone would be crazy enough to break into the Ministry of Magic.

I don't really understand why. I personally found the other magical schools really interesting. It is one of my many reasons for considering Goblet of fire one of the best written books in the series.

I especially liked the newly introduced foreign characters. Viktor is a very clever and kind boy and not at all arrogant despite being extremely famous. Fleur is first introduced as haughty and condescending but evertually turns out to be a very nice and humble girl.

But they are unfortunately not mentioned much in the later books, especially Viktor. This is one of Rowling’s biggest mistakes with the Harry Potter series. She created and outlined some very interesting characters and then did almost nothing with them.

There are quite a few plot holes in Harry Potter saga.

• Time Travelling & Time Turners

The whole concept of time travelling was unnecessarily introduced in HP. JK could've thought of some other way of handling Sirius's escape. It's not quite brilliant to introduce time travelling in a magical story. Also, the plot was handled poorly and logic was too inapplicable. Why is the ministry entrusting a 3rd year school girl to use time turners properly? Wouldn't have the other wizards and witches misused time travelling for selfish purposes? The end of time turners was also not very satisfactory.

• Wizard-Muggle Relations

If Voldemort is such a big threat to the whole world, why isn't the wizarding world seeking the help of muggles? Muggles could've just nuked Voldemort or declared emergency in Britain. When it's the case of protecting the entire world, is it still important to secure the wizarding secrecy? Even at a time of terror?

• Battle of Hogwarts

I was quite disappointed the way Battle of Hogwarts happened. Did no other wizarding countries come forward to help the Battle? The whole battle was between the teachers of Hogwarts, 7th year students (in which slytherins chose to fight for the death eaters), the order of the phoenix (which is really weak; the only notable members are Moody (who's dead), Lupin, Tonks, Kingsley, Molly, Arthur, Bill, Fleur, Charlie, Fred and George) against thousands of Death Eaters, giants, acromantulas, dragons and what not? It should've clearly ended up in favour of Voldemort.

• International Wizarding Congress

Why did no single country turn up to help Britain? What was American Wizarding Congress doing? What about Beauxbatons or Durmstrang? Other Asian and Australian wizarding communities? Why did no one give two shits about Voldemort? Did they just leave Britain to deal with their own business and planned to act only when Voldemort threatens their own countries? Is that how wizarding systems work?

• Employment at Wizarding World

In Wizarding World, you have very limited amount of job opportunities. You can either join the ministry of magic, or run a shop, or become a teacher or study dragons, plants, magical animals or become a quidditch player or become a death Eater. What else is there? There isn't option for creativity. There isn't an option to build magical architecture. There isn't an option for broad mindedness.

• Healing

The wizarding community is advanced enough to mend broken bones in a single night but can't cure bad eyesight.

• Classes at Hogwarts

There are a total of 9 main Hogwarts classes upto the fifth year. Transfiguration, Potions, Defence Against the Dark Arts, Charms, Herbology, Care of Magical Creatures, Astronomy, History of Magic, Divination/Ancient Runes, Arithmancy (optional). And there are 5 lessons a day. If a lesson needs at least 3 classes, how does that fit in a single week?

Harry, Ron and Hermione spent around 2 months planning their break into Gringotts, but none of them realised that they could have destroyed the Hufflepuff Cup Horcrux with the Sword of Gryffindor inside Bellatrix’s vault.

Harry even touched the Cup with the Sword as the Gemino and Flagrante curses meant that he couldn’t touch any of the treasure with his bare hands.

They were so stressed about “double-crossing” Griphook, that this obvious solution never crossed their minds. Of course it would have led to the loss of the Sword, but, not knowing the other Horcruxes’ locations, that would have been of secondary importance. Furthermore, having destroyed the Cup, they did not require the use of the Sword again.