I don't personally see why anyone would dislike poor players simply because they were bad - surely the fault lies with the person(s) as a result of whose judgement the bad player is in the team. And I don't see why people dislike a player because he's overrated; surely there, the fault lies with fans who are predisposed towards limited by hard-working players simply because they put in a shift.
No, there has to be something else for me to make a player dislikeable. Usually, it's been the players who came to us with a decent pedigree and who quite blatantly ended up just taking the money, putting in the minimum effort, Danny Mills being the most egregious example for me. I took against Ben Thatcher because his challenge on Pedro Mendes was the kind of thing I don't like to see any City player do (I don't care if players from other teams are guilty of equally reprehensible acts), and Joey Barton was similar.
However, while I don't hold being crap against a player, I do when they have Barry Silkman syndrome. He replaced Brian Kidd, a seasoned top class striker who was still only 30 and whose strike rate during a little under 3 seasons at City was better than a goal every two-and-a-quarter league games. Silkman wasn't fit to lace Kidd's boots, yet obviously saw himself as a Rodney Marsh-style entertainer and would swan around as if he owned the place.
I think even his detractors would concede that Marsh had considerable talent to back up such a claim. It used to infuriate me to see Silkman, surrounded by experienced top-class professionals, treating himself as the star turn, with embarrassingly poor returns. In enraged me even more when we sold off the star players over the summer of 1979 and that fucking clown continued in the senior side at the start of the next campaign.