In the early days of her tennis career, Serena Williams cared so much about winning that she forgot to collect her earnings — repeatedly.

Williams, 42, brought in $94.8 million in prize money as a tennis player before retiring in 2022, according to the Women's Tennis Association. Early in her career, she nearly left a decent chunk of it behind: She was so singularly focused on her performance that she'd nearly leave cities without picking up her money, she told First We Feast's YouTube talk show "Hot Ones" last week.

"Is it true that you rarely collected your winnings your first year on tour and then once tried unsuccessfully to cash your first million-dollar check in a drive through ATM?" host Sean Evans asked her.

"Those are all true," responded Williams, who won 23 Grand Slam singles titles and 73 career singles titles during her 27-year career. "I never played for money. I played because I loved the sport ... I wanted to win."

Williams' professional debut — in which she played a single game, losing a qualifying match at the 1995 Bell Challenge in Quebec City, Canada — reportedly resulted in a $240 check. At age 14, she was in no rush to spend that money, she said.

The same was true when Williams got her first million-dollar check. People around her were excited about the dollar figure, but all Williams wanted to do was deposit it and get back to work, she recalled.

"I never really spent a lot of money," said Williams. "I just went through the drive-thru and the guy was like, 'Uh, I think you need to come inside for this.'"

As her career evolved, her "tax guy" had to remind her to get her money while she toured, she recalled.

"[He] would be like, 'You didn't get your money?' And I'm like, 'Oh, I didn't get that one in Zurich. I forgot that one in Moscow,'" Williams said. "I was playing to win, and if I didn't win, I wasn't thinking. I was just so angry that I wanted to just figure out a way to get better and win the next time."

When to teach kids money lessons

Williams' early-career experiences were part of her financial literacy education: When she started making her own money as a teen, her dad Richard made sure that she was in charge of it, she told Bloomberg's 'The Deal' podcast in May.

"I remember having to figure that out and having to learn how to manage from a very early age and not get crazy with it, and so he empowered us to do that," Williams said, adding that when it came time to weigh sponsorship deals with companies like Puma and Nike, she always had a seat at the table.

"I'm 16, my dad is negotiating, they're going back and forth, and he wants me there for the whole time to make sure I know what to do in the future," she said. "I learned early on that your paycheck from tennis — maybe that's why I forgot them — should be your smallest earning."

Personal finance lessons for kids are important, experts say. If you start teaching kids basic money lessons as early as ages 5 to 8, they'll be ready to learn about concepts like saving, spending and investing by ages 8 to 12, Eric Landolt, head of family advisory and art & collecting at UBS Global Wealth Management, told Make It last year.

By the time they're teenagers, they'll be well-equipped to effectively manage a small budget or allowance, said Landolt.

"Financial literacy should be a basic skill, a basic skill in the sense of like, reading or writing or doing so something in a way that should be brought to everyone in any circumstance," he said.

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