By Molly Triffin

Paying your dues may seem old-school to many these days, but there are some surprising benefits to grunt work. Not only did plenty of super-successful people start on the lowest rung of the ladder, but their early experiences in low-level positions frequently seeded their path to success—whether inspiring future projects, teaching them valuable workplace lessons or offering low-risk opportunities to up their game.

Check out how these seven went from small potatoes to success stories.

Jeff Bezos: McDonald’s Grill Man

The Amazon head honcho landed a summer job in his teens as a “grill man,” flipping burgers at McDonalds. Aside from honing the ability to crack an egg with one hand, Bezos gleaned a lot from what many people would consider a mindless gig.

“You can learn responsibility in any job, if you take it seriously… It’s different from what you learn in school. Don’t underestimate the value of that,” he says in “Golden Opportunity: Remarkable Careers That Began at McDonald’s.” “The most challenging thing [while working at McDonald’s] was keeping everything going at the right pace during a rush.”

Warren Buffett: Paperboy

At 13, Buffett woke up every day at 4:30 a.m. to deliver copies of the Washington Post. But he was a far cry from your average paperboy, taking an ambitious approach to his route that hints at the incredible drive and savvy he wields now.

According to “The Snowball: Warren Buffett and the Business of Life,” he brainstormed strategies to deliver his papers as fast as possible, sold calendars and magazine subscriptions on the side and took in $2,000 in two years. At 15, he hammered out a profit-share agreement with a farmer in Nebraska and invested $1,200 of those earnings in a 40-acre farm. So, uh, not exactly your average teen.

Marissa Mayer: Supermarket Clerk

Where did the former Yahoo CEO first learn the value of hard work? It wasn’t as a coder, product manager or VP for Google—but at the County Market in Wausau, Wisconsin, where she worked as a grocery store clerk at 16.

“Many of the cashiers had years of experience and were very committed to their jobs, so I saw firsthand the importance of a great work ethic,” she told Fortune. “I learned that speed mattered… The only way to be eligible to work an express lane was to do 40 items per minute consistently. I also learned a lot about family economics, how people make tradeoffs and how people make decisions on something fundamental, like how to eat.”

Michael Bloomberg: Parking Lot Attendant

Hailing from a middle-class family in Massachusetts, the billionaire businessman and former New York City mayor worked as a parking lot attendant to help pay for his tuition at Johns Hopkins University.

Maybe that’s why he made traffic policy a hallmark pursuit as a politician. The “MetroCard mayor” pledged to commute to work via mass transit, promoted bike lanes and a bike-share program in NYC and created exclusive high-speed bus lanes. More recently, Bloomberg has emerged as a champion for global road safety, dedicating $250 million from his charitable foundation to improve conditions and promote bike and mass transit use around the world.

Beyonce: Salon Sweeper

These days, Queen B has a full-time glam squad at her beck and call. But she’s revealed that she was once on the other side of the curling iron at her mom’s Houston salon.

In addition to earning spending money, her conversations with clients drove home the message of female empowerment that later made her a feminist icon in addition to a music mogul. “I grow so much from…[having] a conversation with a woman who understands me,” she’s said about her time at the salon.

Doug McMillon: Walmart Truck Unloader

Here’s proof that you really can work your way from the ground up: As reported by Business Insider, Walmart’s CEO and president started at the company in high school, unloading trucks at a distribution center in his home state of Arkansas.

Post-college, he was hired as a buyer trainee while working his way through grad school. Armed with an MBA, he landed a position at the Bentonville, Ark. headquarters and rose quickly through the ranks as a buyer, merchandise manager and senior VP. He snagged a major promotion in 2006, when he was named CEO of Sam’s Club, a Walmart subsidiary. Three years later, he was put in charge of Walmart International, where he grew international sales by 29 percent. In 2014, he became the company’s fifth CEO.

Shonda Rhimes: Candy Striper

Long before “Grey’s Anatomy” catapulted her into superstar producer territory, Rhimes was a candy striper—which directly influenced the creation of her first hit drama.

“It felt like there were a thousand stories in every [hospital] room and there is something really great about that idea,” she told PEOPLE. “And then surgery, just the idea that you could hold a human being’s heart in your hand and you are responsible for life or death… I felt like [doctors] were warriors. That was really intriguing for me.”

Word is still out on the inspiration behind McDreamy.

Originally published at grow.acorns.com

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