When billionaire entrepreneur and investor Mark Cuban started his first business, he decided to go all in. So all-in that he didn’t take any time off for nearly a decade, he says.

“I didn’t take a vacation for the next 7 years,” Cuban told “The Playbook,” a video series published by Sports Illustrated and Entrepreneur, in an episode that published on June 3. “All I did was learn, learn, learn.”

Cuban launched his first startup, a software company called MicroSolutions, at age 24. At the time, he was sharing a three-bedroom apartment with six roommates and had just lost his job at a computer software store. The situation made it easy for him to find the drive to build a company, he said.

“I was broke as f---,” said Cuban, 66. “I’d always been entrepreneurial, but that’s motivating. I only had one direction to go, and I wasn’t going backwards.”

Cuban was so single-minded in his efforts to build his business that he refused to take any time off, he said. He never would’ve reached his current level of success — starring on ABC’s “Shark Tank” for 14 years, owning a stake of the NBA’s Dallas Mavericks since 2000 — if he’d attempted to have a work-life balance, he added.