Oblivion. I sucked at aiming the fireballs, since I played it when I first got into console gaming. I don't think I hit a single wolf with a fireball. On top of which, I have a bad habit of jumping around when I travel, which came from my Counter Strike days. Of course, that meant my acrobatics kept leveling up, which made me a level 6+ with no other skills, and then the monsters leveled with me, which I didn't know when I started. Add to that, I was paying on a PS3. Same problems when I tried Fallout 3. I haven't even bothered with Skyrim because of the two.
Most FPS since Counter Strike. I used to play hours a day in college. I think since then, I've only been able to sit through "Borderpost", Bioshock 1/2... And Rage, but barely. Don't know why I lost interest in it, since it used to be mostly what I played, from Wolf3D through Half-Life.
FFXII. Gambits sucked. I really wanted to like it, cause I loved FFTA, which bruins me to...
FFT. Played about 60% of it, and just stopped. I just never connected with any of the characters.
Makai Kingdom. I actually love must things about this game, even liked it more than Disgaea. But everything in the game feels like it takes 5 minutes to do. If it had a fast forward feature, I'd go back instantly.
Odin Sphere, only because of the load times. Tiny stages made play time and wait time practically equal.
Bastion. I don't know how it got such high praises. The narration and art were absolutely awesome, but the game itself was meh.
Thief. I got stuck in the second level with the skeletons, moss and water arrows. I kept running out, then the skeletons would kill me.