"Never having played the sport, he launched the “Dan Plan” to golf for 10,000 hours and eventually earn a spot on the U.S. PGA Tour."'via Blog this'
The 10,000 hours references this book:
Outliers: The Story of Success (Kindle)About Outliers (Wikipedia) - it references a study that suggests it takes 10,000 hours of deliberate practice to master any skill.