This Devastating Financial Mistake Shaped Kevin O'Leary's Future Relationship with Money

We think that financial experts like Kevin O’Leary of Shark Tank know everything there is to know about money, but turns out that wasn’t always the case.

Even Kevin O’Leary was once young, and had a lot to learn!

“When I was younger, I made a big mistake. I loved to play craps,” O’Leary tells CNBC Make It, referring to the casino game found in Las Vegas and other gambling centers, “and it was a very important lesson for me.”

When leisure becomes danger

O’Leary was visiting Las Vegas in his early 20s to attend a computer expo trade show for his that-time work in the computer business. He ended up burning off some steam at the end of a long day at the expo by playing craps until the wee hours of the morning. It didn’t go so well.

“So there I was, sitting in the casino, 2 in the morning, rolling in the craps table — and I had practically no income [then],” O’Leary says. “And I blew myself up. I ended up in debt that night, tens of thousands of dollars. And back then, that was everything.”

That sounds horrifying to us, and it was to him. But he learned from it. “It was a very important lesson,“ O’Leary recalls. “I paid it all back, it took me a long time to do it, and I never rolled the dice again.”

After that day, he swore off gambling. “Sometimes in life it takes an extraordinary experience like that to set you straight,” he adds. “I don’t take chances like that anymore, ever.”

However, that moment shaped his future in a big way. He’s no longer reckless with money, in fact he’s very conservative as an investor on “Shark Tank,”  and speaks of the value of saving, investing and paying down debt.

“I love money,” O’Leary says. “I get emotionally involved with it. I feel warm and fuzzy when I have lots of it.”

Don't we all!