Kobe Bryant shares the No. 1 lesson he learned from Oprah, Tim Cook and other successful people

Kobe Bryant doesn't hesitate to reach out to other successful people. "What I love doing is cold-calling people," the former NBA star told CNBC in 2016. "What did you read? What did you learn? How did you learn it? Those are the questions."

He's learned a lot from three people in particular, he told Alex Rodriguez and Dan Katz on a 2018 episode of "The Corp": media mogul Oprah Winfrey, Apple CEO Tim Cook and Nike CEO Mark Parker.

"Those three are the biggest ones that have had the most influence in what I'm currently building," said Bryant, who retired from basketball in 2016 and is now focusing on growing his production company Granity Studios.

The key takeaway from his conversations with Winfrey, Cook and Parker is that even the most successful people trip up: "We tend to look at them and say, OK, they don't make mistakes. They don't make bad decisions. That couldn't be any further from the truth."

Bryant heard about some of Winfrey's missteps right before creating Granity. "When I had the idea of first starting a studio, the first person I called was Oprah Winfrey," because she founded her own production company, Harpo Studios, in 1986, he recalled.

"We sat on the phone for about an hour and a half, two hours — went through the history of building Harpo and the things that she felt she did well and the things she felt like she didn't do so well," Bryant said. "She walked me through her journey to help me on mine."

Talking with Cook and Parker reiterated that "we all make mistakes," said Bryant. "We all make decisions. And you just continue to plow forward. You continue to figure it out."

Self-made billionaire Richard Branson agrees, and is often open about his failures. "There's only one thing that is an absolute certainty in business: We all make mistakes," he writes on his blog.

"Nobody gets everything right the first time," Branson writes in another blog post. "Business is like a giant game of chess — you have to learn quickly from your mistakes."

Bryant, who won an Oscar in 2018 for producing the Best Animated Short Film, "Dear Basketball," says that success boils down to a growth mindset. He told CNBC in 2016: "To grow, you have to constantly learn, you have to constantly move, constantly improve. That's the key."

Plus, "That's what makes life fun."

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