10,000 Hours

I read an article at the weekend that claims it takes approximately 10,000 hours of practice to become really, really good at something. It could be anything - music, elite sports, computer programming. Bill Gates spent more than 10,000 hours playing around with computers before he became the genius of Microsoft. Mozart spent 10,000 hours playing the piano before he became, well, Mozart. That's about three hours a day for ten years.

Gulp. I wonder how many hours I've spent writing?