To solve this problem I've decided to never spend more than a week making a game!
Okay, that's not really the solution to my short attention span. And it's not really the plan for the rest of my life. But at this stage in my game development career, the two most important things for me to do are 1) get experience making games, and 2) build a portfolio of finished* projects to show prospective employers, teammates, and my legion of devoted fans.