I dislike when the super obvious villain is super obvious, but no one notices. But that happens in everything, so
rolleyes Also some anime sorta has this thing where when an anime ends, it not really an ending. Like everything will carrying on as usual, even though some huge life altering event just happened. At least have some semblance of weight or something.
Also when reverse harem shows suck. Ouran High School was probably the best. Then comes Brother's Conflict (
And lastly, when you watch a series and like it but the anime either ends up going nowhere or the ending just somehow doesn't mesh with the rest of the anime. This one is big one for me. I'll either find it a chore to get through the anime or choose not to complete it. Or watch the second season. . . (Sorry Tokyo Ghoul. I realize many will disagree with me on this point, but that ending! It was so bad.)