Well look at the PS2. They had like 90% (I guess) of all games on the PS2. Practically every game that came out from a 3rd party was either exclusive to the PS2 or at least on the PS2. And everyone bought the PS2 even tho it had the weakest hardware, simply because it had the most games, so no matter what games you like, there were probably 100 of that type on the PS2 already.
Also if companies put good games out they will sell better, so eventually the quality will get better. When companies see that other companies are making lots of $$ with a great game, or when they see their good games outperforming their crap games we will see more good games.
The crap games will still be there, but who cares. Some people will like any game even if other people dont.