Conduit: Glitches, Online hackers, story was lame, Wii speak sucks on it, people were disappointed with it, boring, short, ASE was underused and used in a boring way, the graphics in areas made the game look unpolished and not finished.
Madworld: Odd game, really short, people found it boring, nothing to do after you are finished, black and white isn't that appealing to a fair number of people.
Dead Space: games sales for the series aren't usually that great and usually pretty creepy horror games don't that well (look at Fatal Frame and Silent Hill as examples, No ads for the game (the game was very silent when it came out), and making it a rail shooter was a bad idea ( a fair number of people complained that it was a rail shooter)
No more heroes: Odd games again, unresponive controls at time, graphics look kind of ugly, overworld, being forced to do boring jobs, no ads for the game really either, and grasshopper games don't usuauly sell anyway (just look at their history).
No More heroes 2: No ads once again, fans that were disappointed with the first one and would try to avoid it, The bosses aren't as memorable as the first one, people were disappointed that henry didn't used much at all, Shinobu is hard to control, Final boss was easy mostly (with epic fight with henry at the end of the first game of course you would be disappointed with this fight)
Red Steel 2: Same name is gonna make people want to avoid it, Piracy, there could of been more ads for it (really if this is suppose to be Big Game then treat it like one)
Resident Evil Darkside: people wanted a real remake of RE2 not a rail shooter, same name makes people want to avoid buying it, shaky camera, lack of good promotion and boring gameplay.
House of the dead overkill: Piracy, too short, boring, frame rate dips. graphics are weak, odd game,
Cursed Mountain: No promotion hardly, unresponive controls (people have complained about it), It is in creepy horror genre (look at Silent hill and Fatal frame as examples)
Silent Hill: no promotion, it was ported to ps2 and psp, some people didn't like that you didn't have weapons, and silent hill games don't usually sell well.