developers problems on the Wii are mainly this. They are making games they "Think" people will like and buy. For the HD systems, they are making games that they themselves like and want to play.
so besides being on the guessing side can make you make a game that people won't like tehre is also the problem of qualiyt. I dont' care what you say. When you are making a game that you are going to like and want to play versus a game made for others, youa re going to put more care into the game you like.