+sonikku956
That´s most likely just a translation error.
Earthling and human share words in japanese, and Tien is also confirmed not to be human, but from race called cyclops.
Toriyama most likely wanted to say the strongest human, leaving Tien outside of the competition. That is way more logical because he didnt say that Krillin was the strongest like it was a big deal, he just mention it. (That´s still wrong anyway, because Uub exists)
Also, Tien trained from the entirity of DBZ and Krillin just now in DBS started to train again.
And every time Krillin and Tien were compared in strenght, Tien was way superior. (When Bulma get the scouter, and when Nappa scout the Z fighters)
I find hard to believe that Krillin has better fisical qualities than Tien, tien can multiplies his arms, is way taller, which means more range, and has a way more physical fighting style. Krillin relies more on his speed and ki attacks.
Also, needless to say, Tien has way better feats than Krillin. Tien fucking rocks.