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Long before Joey Zwillinger founded his $1.4 billion shoe startup, Allbirds, he was a lift operator at a ski resort in Tahoe. “It was my first job and my worst job,” he recalls. “They gave me non-waterproof gear and it was the rainy season and I was soaked and dealing with angry parents and children, who’d been waiting in line.”

Parisa Tabriz, senior director of engineering for Google’s Chrome, was a lifeguard at a local pool: “I saved a baby bird from drowning in the lazy river, and I cleaned up nacho cheese spills from the concessions area.”

Turns out even the movers and shakers on Fortune’s 40 Under 40 list had some ho-hum jobs when they were younger. Peloton cofounder Tom Cortese valet-parked cars. Presidential candidate Pete Buttigieg walked dogs. Sam Rapoport, senior director of football development for the NFL, worked at a golf course—a job which required her to leave the house at 3 a.m. But those early jobs can offer some important takeaways and, as our 40 Under 40 honorees found, can pave the way for success down the road. Read on to see what several of them had to say about their first jobs.

Cal Henderson, 38

Cofounder & CTO, Slack

I worked in the local pub. I washed dishes, served food. Our customers were part of the community, they would come in almost every day for lunch or after work. I learned a lot about how service and relationships are as important as the product itself when you want to offer a good experience.

Kate Gulliver, 37

Global Head of Talent, Wayfair

My first job was scooping ice cream as a teenager. (I eventually became the manager!) I learned a lot about customer satisfaction and how to work with—and then ultimately manage—your peers.

Mei Mei Hu, 36

Cofounder & CEO, United Neuroscience

(My first job was) selling knives door to door. It made me face a lot of fears and learn how to pitch strangers, deal with rejection, and close a transaction.

Alyson Friedensohn, 29

Cofounder & CEO, Modern Health

My first job involved painting nail-polish on rocks and convincing kids in my neighborhood to buy them as pet rocks. Yes, I was hustling from the age of 9. I realized my total addressable market was limited by selling (for) 50 cents goods that took me hours to make. This led me to my next job, which really took me to the next level of selling—my first lemonade stand.

Tim Brown, 38

Cofounder, Allbirds

(I was a) window cleaner. It was pretty bad. I … was working in a design office—which was a subject area I was becoming interested in—and I was trying to talk to the people in the offices. Then I was told not to talk, just to clean the windows. What I took from that was the feeling of trying to not make anyone feel invisible.

This article is part of the 40 Under 40, our annual selection of the most influential young people in business. Click here to see the additional 2019 coverage of these disruptors, innovators, rebels, and artists.

Selling Knives, Lazy Rivers, and Dive Bars: Here’s Where This Year’s 40 Under 40 Got Their First Jobs

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