After graduating from Indiana University, Mark Cuban moved into a three-bedroom "dump" with five friends and worked as a bartender to make ends meet.
At age 32, he reached millionaire status when he sold his first company, MicroSolutions, and at age 40, he joined the billionaire club after selling his second company, Broadcast.com. Today, the entrepreneur owns the Dallas Mavericks and has an estimated net worth of $3.3 billion.
According to the self-made billionaire, following your passion is overrated.
At a day-long conference last week in San Diego sponsored by Clever Talks, Cuban exposed three of the biggest misconceptions about running a successful business, reports Lori Weisberg of The San Diego Union-Tribune.

Myth 1: You need to raise a bunch of money after you come up with an idea
Rather than focusing on funding, focus on sales, the billionaire advises: "In every business, sales cure all."
Self-made millionaire Grant Cardone shares that philosophy. Above anything, focus on earning, he tells CNBC: "People get rich because they produce revenue, not because they make little investments over time."
Myth 2: You need to find a mentor
"I'm not Mr. Mentor," says Cuban. "A lot of people looking for mentors think, 'Here's the magic dust.' Just get out there and sell something."
Myth 3: Following your passion is a recipe for success
This mainstream career advice won't necessarily lead to success, Cuban says: "Ask yourself, 'What do I have that makes it a no-brainer for people to buy from me?' If your answer is, 'I'm passionate,' you're in trouble."
He's not the only one to say you "do what you love" is bad advice. As CEO of MailChimp Ben Chestnut tells The New York Times: "It should be, 'Love what you do.' Take the job, learn to live in the moment and love it, master it, and doors will open for you if you're good at what you do. Turn it into a passion if you can."
