My job, as GM, is to create a self-consistent and interesting world in which the players can have their characters adventure. I do not consider it my job to make sure that the players I have are having fun; rather, I consider it my job to find players who find the same stuff fun that I do. If that means some players leave my group because our tastes don't match, that's cool; if they're worth having to my home for a game, they're worth getting together with over a beer outside of gaming so it's not like I lose touch with interesting people who try my games and find their tastes don't match mine.