My biggest offender is Civ 5. I've got like, 200 hours in that damn game, so I cant say that I hate it or anything, but I really dislike so many parts of it. Mostly the AI being utterly terrible, and the online being a pile of poop 80% of the time.
But from time to time I still play it. Mostly because my friends like it, and it is still addicting enough despite its huge flaws