Kevin O'Leary is known for giving his fair share business advice as an investor on ABC's "Shark Tank," but he gleaned some good tips himself from an unlikely source: Rolling Stones lead guitarist Keith Richards' memoir, "Life."
"People ask me all the time which business books I am reading, and the one I'm finishing that I've been working on for a long time is Keith Richards' autobiography. If you want to learn about business — read that book," O'Leary tells CNBC Make it.
As one would expect, the 564-page book, which was released in 2010, chronicles the rock legend's wild ride to stardom, from the Rolling Stone's early struggles, to Richards' often turbulent relationship with lead singer Mick Jagger, to his dark days battling drug addiction.
But the book isn't all sex, drugs, and rock-n-roll, according to O'Leary. He says it's filled with life and business lessons too.
"[Richards] learned how to deal with life in unique ways, even in the good times and the bad times," which is an essential skill for anyone who aspires to be successful in business, O'Leary says.
For example, after having some very public fights about the direction of the band, Richards and Jagger realized that they would likely be less successful as solo artists than they were as members of the Stones, so they found ways to feed off each other's energy. The experience taught Richards a lot about leadership.
"I don't care who's leading, it's about whatever is best for the team," Richards writes.
Richards also writes that there are no shortcuts to success. Early on, even the Stones had to work gig after gig for free to gain experience in the early 1960s, and as their fame grew, they still performed two gigs a day for three years straight, taking off only 10 days. And they're still performing today, half a century later.
It's an ethos that O'Leary also espouses: You have to "work 25 hours a day, seven days a week, forever," O'Leary previously told CNBC Make It. "That's what it takes to be successful."
The Rolling Stones' 2007 "A Bigger Bang Tour" was one of the highest grossing tours in history, earning $558.2 million for 144 shows, according to Billboard. Yet Richards, 74, says in the book that he's not in it for the money.
"People say 'why don't you give it up?' I don't think they quite understand. I'm not doing it just for the money, or for you. I'm doing it for me," Richards writes.
O'Leary also believes success is not about the money: "It's a long, hard journey, but it's worth it," O'Leary has said. "It's not about the greed of money, it's about the pursuit of personal freedom. If you're successful as an entrepreneur, you will set yourself free...."
But O'Leary says the biggest thing he learned from the memoir was that even Richards' most horrific outcomes — including a drug addiction that almost killed him — didn't stop him from reaching his goals, which is one of the most important business lessons.
"[It's] the best business book on the market and I know that sounds crazy [but] check it out," says O'Leary.
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Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."