I guess I've a very specific taste which causes me to dislike a lot of the anime I watch even after I selected them based on my general taste beforehand. Too unrealistic individuals and actions, a good 3/4 of all anime I would say. Too sexualized, sorry but I don't get turned on by cartoons, a good 1/8 of all anime I would say. Way too annoying voices or a very weird animation style by my taste, a good 1/4 of all anime.
Shows like Mayoi Neko Overrun, Date A Live, Nyan Koi. They are just not my thing. I'm sure they will entertain other people so I'm not too bothered by the fact that I don't like them. I usually know if I'll watch all of a series or drop it immediately after the first episode anyway. I should note though that I don't really watch a lot of anime, about 100 hours in 1.5 years.