Lucy Guo, co-founder of artificial intelligence startup Scale AI and the world’s youngest self-made woman billionaire, said displays of luxury are more common among millionaires than billionaires.

"I fully admit it, I have gone through that spending spree when I was more insecure, and I felt like I needed to show something," she told Fortune, referring to her past use of a luxury Patek Philippe watch and a Hermès Birkin bag. But she said she has since moved beyond the need to project wealth.

Guo joined the ranks of the world’s richest in April when Forbes estimated her net worth at US$1.3 billion, placing her ahead of pop star Taylor Swift as the youngest self-made woman billionaire.

Guo said those who often spend on designer goods or luxury cars are typically in the millionaire tier. "All their friends are multimillionaires or billionaires, and they feel a little bit insecure, so they feel the need to be flashy to show other people, ‘Look, I’m successful,’" she said.

She also noted that growing criticism of billionaires in the U.S. leads many wealthy individuals to downplay their lifestyles. "People want to show, ‘Look, I’m not your typical billionaire. I’m frugal.’”

The 30-year-old entrepreneur has spoken publicly about her modest upbringing, including her early business selling Pokémon cards at school, according to Entrepreneur magazine. Today, she drives an old Honda Civic and shops at budget retailer Shein, keeping a few designer outfits for special occasions.

She told Fortune she believes most billionaires adopt a casual style because they no longer need to impress others. "They don’t need to be in the suit 24/7 because they’re done proving themselves to the rest of the world. The rest of the world is just sucking up to them," she said.

"And I think that’s kind of how I like feel, where I’m past that hump. I don’t really have to prove myself to anyone."

Guo co-founded data-labeling firm Scale AI with Alexandr Wang, 28, currently the world’s youngest self-made billionaire with a net worth of $3.6 billion. Meta has invested in Scale AI in a deal that values the company at $29 billion, with Wang joining the tech giant to help lead its artificial intelligence strategy, Reuters reported on June 12.

Guo is now CEO of Passes, a platform she launched in 2022 to help digital creators monetize their content. The company raised $40 million in a Series A funding round earlier this year. (VnExpress International, but headline rejigged)