I've been in the android market for a year and have done over $100k in sales of my games, and you hit the nail on the head. Create lots of games, and not just for the money. You have to be having fun while creating or it becomes a miserable job. I'm falling into that rut myself, and because I've spent so much time working on my flagship game, I've gotten behind. Competition of that game has increased, sales have slowed down, and I'm scrambling a little now to get my other games polished and selling at a higher rate.

All the while, I'm sick that I'm not loving what I'm doing anymore as I chase the dollar. I think it's time for me to reboot and spend my time on a game I've always wanted to play and make. If I love doing this again, my success will sustain itself.