It could have very much so changed the outcome of the game, and it could have injured someone. That's the point. If someone fails at blowing up a school, people don't just go "oh, well no harm done" and move on. It's the fact that they attempted to fuck something up.

And before you try to straw man me, no, I am not comparing throwing a beer can to blowing up a school. It's an example to show how flawed your logic is.