The sales are NOT disappointing, I'm completely shitting on the game at this point, I have it right here next to me, I'm not just parroting other people here. The camera is fucking God awful, they didn't even bother to fix it, the graphics are terrible, the story itself is bleak and has terrible character development. The game allows you to miss out on sub-quests easily because it's so confusing as to what's going on. It also limits your time, that aspect of game design was in purely to give a sense of urgency and to promote replayability for a portable title that couldn't fit much onto a UMD.
You wonder why I have this attitude for the sales, it's because I think the game in many ways is shit. It's a mediocre/sub-par game that somehow got its way up to #10 on this list... again... not disappointing.