Quite a few games really.
-Tales of Symphonia I loved when I first played it, but when I tried to go back and replay it I really didn't like it.
-Halo games. The first game was really enjoyable, the second game's online was enjoyable(The single player was a bit meh...), once Halo 3 was released however I really didnt like the series, can't play the first 2 now either, they all seem monotonous.
-Bioshock. Thought it was going to be like most generic FPS' however to my enjoyment, it wasn't and it turned out to be one of my favourite games of that year.
-Kingdom Hearts. I've changed my mind so much about that game its crazy. Started out really liking it, playing it for hours. Then I went off it as I really got bored of all the monotonous Disney worlds(I've never been a big Disney person, so there wasn't any nostalgia to help me along either...) Perservered with it, and started really liking it as it got to the end and more of the real story was revealed. Really loved the ending too. Same happened with KH2, loved the first few hours when you play as Sora's nobody(Forget his name) and then you go back to playing as Sora in the diney worlds and it becomes a bit monotonous again. I've come to the conclusion with that, I just really find those disney worlds boring.
-Fable 2. Adored Fable 1, and I've completed that loads of times. So I was really anticipating the release of Fable 2. I was on holiday when it was released, but it was waiting for me when I returned to England. Shoved it in, and loved it in the beginning, the opening was a bit reminiscent of 1, but I still loved it. I played through it, anticipating some awesome story event as it was building up the storyline for something climactic to happen. Then I get to the ending, which to me didn't even feel like an ending. It felt like someone started writing a story and got sidetracked halfway through, not finishing it, or they forgot to add the second half of the game. Really did kill the game for me, I can't play it again either because of the knowledge that it ends lackluster. It is all very well saying DLC is going to be released, but I paid £40 for a full game, not an half completed game.. =/