Every Kingdom Hearts game excluding the original, and possibly Chain of Memories (which loses massive points for linearity).
But I'm gonna focus on 358/2 Days because god damnit is that game a mess.
358/2 Days has one of my favorite video game endings ever, especially since we all knew what was going to happen. However, the game has without a doubt the most mashy combat in an already mash-heavy series, it outright recycles and cuts the corners on the bad KHII levels, and the way we get to the ending is more or less a solid 20 hours of people running away from the call.
Granted, I found the pace of "Go to 'work', finish, see little character moments," was a refreshing change of pace from typical video game story, and that combined with the diary made it a far more intimate experience. However, there's just enough of Xion not being around causing shit not to happen to really, really get on my nerves, and frankly, I really like that character. It's a damn shame that the combined ending of this and then Kingdom Hearts II end up killing the most interesting parts of the KH universe.
Oh, wait.
Anyways, honorable mention also goes to Birth by Sleep, because, as opposed to 358/2, I cannot think of anyway that that travesty could've been any better. Or rather, I can think of so many ways, but only in ways that fundamentally change the game that was made, whereas 358/2 really needed some editing and originality whereas BbS needs a complete, ground-up redesign and the script needs to be burned in the same fire in which someone should also place the US tax code.