I wasn't going to inflict yet another Twyla Tharp quotation on you, but right at the end of the book, she says the following:
The libraries and museums are packed with early bloomers and one-trick ponies who said everything they had to say in their first novel, who could only compose one good tune, whose canvases kept repeating the same dogged theme. My respect has always gone to those who are in it for the long haul. When people who have demonstrated talent fizzle out or disappear after early creative success, it's not because their gifts, that famous "one percent inspiration," abandoned them; more likely they abandoned their gift through a failure of perspiration.
Bam. The perfect antidote to the cult of the young and dizzyingly talented. There was a feeling during my college years (at least, I had this feeling) that if you were any good you'd be published in your twenties. No one talked about the long tail. No one talked about the best full-time jobs for writers who were not going to earn a living wage from their writing immediately after college (i.e., all of us). No one talked about getting better as you get older (well, Margaret Weis did one time...).
But that's the truth for almost all of us word slingers who do eventually become "successful." That's the only truth. We just don't stop writing.