Theory: Introverts thrive on ideas. Extroverts thrive on presenting ideas to the outside world. Introverts fall in love with the ideas themselves and how it makes them feel to have the idea. Extroverts fall in love with the outside world's reaction to the idea and how it makes them feel when others love the idea.
This explains the death of my motivation as a writer. I fall in love with the ideas, but presenting them to the outside world-- well, that's pretty much a buzz kill. This explains why my ideas so often don't get off the ground. This and the fact that I am a lazy human being, who most days can't bring myself to do much more than loaf.
And also, the sensitive little asshole that I am, I can't handle rejection (boo hoo, right?). Such is the fate of the introvert-- being a sensitive little asshole who can't stand almost anyone.