“People keep thinking, you learn more from failure,” the 81-year-old tennis legend exclusively told Fortune at the Power of Women’s Sports Summit presented by e.l.f. Beauty. Instead, she says, the top 1% “learn how to win.”

Like Gen Z, who are huge fans of manifesting success, King agrees that there’s power in thinking positively. “If you think you’re a failure, you’ll fail. If you think you’re a winner, you’ll win,” the American former world No. 1 women’s tennis player said. 

But in her eyes, there’s more to manifesting than telling yourself “I’m lucky” until it becomes reality. More logically, the reason why people who call themselves winners go on to do well is because they anaylze what their strengths are and what makes them win—and they double down on it. 

“I want people to pay attention when you win: Why did I win? And that’s really important, because that’s how you can keep building, building and building as you grow older and older in life,” King explains. 

“What sentence did I write well? Were you kind to others? All these things are building blocks to have a better life.”

The mindset shift that made Billie Jean King a champion—again and again

Before she became a global icon, won 39 Grand Slam titles, campaigned for equal pay, and then founded the Women’s Tennis Association, King always had an innate belief that she’d be successful. 

Even as a kid from Long Beach, Calif., with a racket, a blue-collar dad, little spare cash, and barely any coaching, King would tell herself she was destined to become the star she is today.

“Here’s how I used to think as a junior player: every time I won a junior match, it was only a stepping stone to be number one in the world,” she told Fortune. “I never thought or cared about junior tennis. Everything I did was to be number one the world as an adult.”

That long-game mentality meant that small wins along the way weren’t the end point—they were study material. Just like after a loss, she would ask herself: What did I do right? What can I replicate?

Fortune’s Orianna Rosa Royle sat down with BJK at the Power of Women’s Sports Summit presented by e.l.f. Beauty.

The habit became a cornerstone of her success, but she says it was really put into practice during a high-stakes Wimbledon match against Tracy Austin in 1982. For the first time ever, King beat Austin, despite being twice her age and a year away from retiring. 

King was fully aware that Austin knew all of King’s moves and would be anticipating her go-to shot (a cross-court shot). So King knew that the only way to win was to go down the line, her weakest shot.

“I knew before I hit that ball, if I didn’t make it, I’d probably lose the match. If I made it, I’d probably win,” she says. She went for it—and it worked.

That moment reinforced a core belief that’s followed her ever since: success comes from understanding exactly what it takes to win. “You have to know why you win,” she says. “I don’t learn more when I lose. I learn more when I win. I think because it keeps me learning how to win, not how to lose.”

For King, feedback isn’t just something you apply after a failure. It’s the habit of asking hard questions after a high, too.

“Everyone should really think about that with their own lives,” she says. “What is your strength? Play to it.”