Bill Holland achieved what many people spend their entire careers chasing: by age 32, he had made enough money to retire for good. But over three decades later, the now-67-year-old still hasn’t hung up his hat.

The former CEO of CI Financial, one of Canada’s largest investment management firms, didn’t take a conventional path to the top. Despite graduating from Toronto’s York University, Holland drifted through a string of self-described “crappy jobs,” like delivering 7Up, working in a factory, and serving as a doorman at a Toronto bar before finding his footing in finance.

At 27, he landed a customer service representative position at Mackenzie Financial Corp.—a demanding job that required fielding roughly 120 customer calls a day, according to a recent profile in Canadian business publication Financial Post.

“People would complain about how hard the job was, but unless you are doing something that involves lifting something heavy, it is not hard,” Holland said.

Within five years, he had capitalized on the booming mutual fund industry and had accumulated enough wealth to retire—a success he attributed to timing as much as talent.

“A lot of people who have disproportionate success, for the most part, are normal people and if they are being honest with you, they will tell you that they got really lucky,” he said. “I got really lucky.”

But instead of walking away, Holland doubled down. He joined a small investment firm with about $50 million in assets under management. That company would eventually become CI Financial, where he rose to CEO in 1999 and later executive chair in 2010. Last year, the company was taken private by the United Arab Emirates sovereign wealth fund and had about $140 billion in assets under management.

Although Holland’s exact net worth is unknown, he accumulated significant wealth through his decades at CI Financial. In 2011, his stake was estimated at $260 million, and he divested fully last year. But his daily routine has remained remarkably unchanged—rather than retiring to a life of luxury, he still commutes to his Toronto office five days a week by public transit.

His work has continued to focus in investing—including in real estate—as well as running his family’s philanthropy office. Over the years, he’s donated more than $100 million to charitable causes.

Even the world’s most successful people, like Warren Buffett and Elon Musk, have maintained habits that predate their fortunes

Holland’s daily commute also puts him in the company of a surprising group of billionaires who have resisted the lavish lifestyles often associated with immense wealth.

Warren Buffett, whose fortune tops $150 billion, has long embraced frugality. In an interview with CBS News last year, the legendary investor put it simply: “I’m cheap.”

That mindset has shaped his life for decades. The 95-year-old still lives in the same Omaha, Nebraska, house he purchased in 1958 for $31,500. The five-bedroom house is now worth about $1.3 million—a tiny fraction of what he could afford—but Buffett has said he wouldn’t trade it because it’s where he and his late wife raised their three children.

His spending habits have also long extended beyond housing. As documented in a 2017 HBO film, Buffett famously let the stock market determine how much he spent on breakfast at McDonald’s. If markets were down, he’d order two sausage patties for $2.61. If stocks were up, he’d splurge on a $3.17 bacon, egg, and cheese biscuit.

Elon Musk, the world’s richest person, has taken a different—and more recent—approach to wealth. For much of his career, Musk lived a lifestyle more typical of a billionaire, owning multiple luxury homes, including several California properties. But in 2020, he announced he was selling most of his physical possessions and began shedding his real estate portfolio. He ultimately sold seven California homes for nearly $130 million after saying he wanted to “own no house.”

The shift coincided with Musk’s move to Texas and his efforts to spend more time near SpaceX’s launch operations. He later said his primary residence was a roughly $50,000 home near Boca Chica, Texas, that he rented from SpaceX. Unlike his previous luxury properties, Musk described the small home as practical because of its proximity to the company’s facilities.

Earlier this year, Musk’s mother, Maye Musk, offered a glimpse inside the home.

“There is no food in the fridge,” she wrote in a post on X. “The garage where I slept is on the right. The shower only has one towel, so I left it for Elon. That was okay with me. When I was a child, I’d spend three weeks in the Kalahari Desert without showering. Many times. There was no water. I think my parents prepared me for this luxury.”

For Holland, Buffett, and Musk, accumulating wealth hasn’t necessarily translated into extravagant spending. Instead, each has, in different ways, maintained habits that predate their fortunes—a reminder that becoming rich doesn’t require living lavishly.

That mindset may also reflect an understanding that success is rarely built on hard work alone.

In a Fortune commentary piece, entrepreneurs and authors Ash Ali and Hasan Kubba argued that while everyone benefits from certain “unfair advantages,” sustained success comes from recognizing and capitalizing on opportunities—not assuming they’ll last forever.

“You can’t fairly say that Elon’s success is a simple matter of luck. You don’t get that lucky four times in a row,” they wrote in 2022.

“The old debate about hard work v. luck takes on a new dimension when you start to see it through the lens of unfair advantages. Musk, like all successful people, simply leveraged his.”