“One of the great lies of life is ‘follow your passions,’” Shark Tank star Mark Cuban says. Reason: you may not excel at what you’re passionate about. “I used to be passionate to be a baseball player. Then I realized I had a 70-mile-per-hour fastball,” says Cuban. Competitive major league pitchers throw fastballs at 90-plus. Instead, Cuban says to pay attention to the things you spend most of your time on, instead of what you’re passionate about. Odds are you’ll be good at the things you put the most effort into, he says.