Making money definitely doesn't take the same amount of practice as piano playing. You won't find a single world-class piano player who started playing when he was 20 years old. But you will find many successful entrepreneurs that started to get interest in making money in their twenties or even later.
The main reason is that luck alone can make you rich, but will never transform you into a good piano player.
It may help you in creating a business if money is your primary interest (e.g. Friedrich Flick), but it will even help you more when you do something that's fun (e.g. Steve Jobs).
Almost nobody practices 8 hours a day, even among world class musicians. (Liszt and his cadre were some notable exceptions.) If you believe Gladwell averaging three a day from ages 10-20 is enough to make a prodigy.
