The Harvard alum and self-proclaimed “accidental entrepreneur” has been on a 10-year-long journey to stock your fridge with the healthiest food options on the market, but at an affordable price point. 

Enter, Thrive: The healthy food membership grocer (think: Whole Foods meets Costco) he launched in 2014 with three cofounders boasts over $700 million in sales and 1.6 million paid members paying $60 per year, according to the company.

Unlike traditional executives who steadily work their way up the corporate ladder, before landing the top job—Green’s path to success began in his Harvard dorm room, where he ran his first side-hustle-turned-business. 

From test prep to million-dollar business

After achieving a perfect score on the SATs—his “claim-to-fame” in his local hometown of Minneapolis city, Minnesota—Green began teaching test prep classes in high school, which later evolved into his own business while still an undergraduate student at Harvard: Ivy Insiders. 

“There were kids in my class that were just as smart as me that didn’t do as well,” he recalls to Fortune. “I had this belief that these tests can be beaten.”

“I basically wrote a curriculum and then hired other undergrads, first from Harvard and then from across the Ivy League, to run SAT and ACT classes in their hometowns,” he says, adding this it gave him a taste of the “full entrepreneurial experience.”

The side hustle paid off: As well as being a fountain of learning, Green was able to pay off his tuition thanks to earnings from the blossoming test prep business. 

“I didn’t take any classes my last semester, and instead, I lived in the dorms and just worked full-time on Ivy Insiders,” he says. In under three years, he grew that business to over 500 locations in 43 states before selling the business to test prep company Revolution Prep for an undisclosed amount.

Thrive Market was turned down by 50 investors—so the founders turned to wellness influencers for cash 

Green met his future Thrive Market co-founder, Gunnar Lovelace, “very randomly through a friend,” he says. Lovelace initially approached Green as a potential angel investor, presenting a “big idea” to make healthy living accessible to everyone by introducing a “Groupon-type model” to healthy, nutritious food. The only problem: customers wanted healthy food items but did not want to wait two weeks for their grocery orders to be filled.

“That was when we stumbled upon the Costco model and started really studying that business—how powerful membership could be as a way to bring prices down, create engagement, and build community,” Green says.

Originally, the two co-founders were going to self-fund the business—having both just sold their prior ventures.

“What we discovered really quickly was that the money goes by fast, that building an e-commerce platform is expensive, that building up inventory is expensive, and neither of us had experience in e-commerce,”  Green says. “Neither of us really appreciated the complexity and capital intensiveness of the model, nor did we expect some of the setbacks that we had that delayed our launch.”

But getting fundraising elsewhere wasn’t easier either: They faced over 50 rejections from venture capitalists before turning to health and wellness influencers to support their initial million-dollar rounds. And Green says it was the “best thing” he ever did. 

“Just getting rejection after rejection after rejection, it became clear: you know, this isn’t going to work. They’re not going to fund this business. They don’t believe that middle-class, middle America wants to get healthy,” he says.

Despite the rocky start, Thrive Market is now thriving

Green says the company’s growth would not have been possible without the membership model: “Membership is really the central core pillar of our business model, because it allows us to offer the products at better prices.” 

This focus on affordability and value is deeply rooted in Green’s upbringing. The son of a middle-class family in the Minneapolis suburbs, Green grew up with parents who instilled careful spending. 

“I knew from a young age that you have to be careful with money. If you want to buy good things, you have to really do the research and find them on a budget,” Green adds. “For me specifically, I saw how hard my mom had to work to do that with healthy food, because there weren’t a lot of healthy options in most grocery stores.”

Looking ahead, Green says that Thrive Market’s rapid growth is just the beginning, highlighting the vast potential for expansion in the health and wellness sector.  

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His advice for those looking to emulate his entrepreneurial success?

“There’s no categorical, ‘this business is good’ or ‘this business is bad,” he said. “It’s about finding a business that’s the right fit for you as an entrepreneur—one that you connect with personally and that calls you to something higher that you truly believe in.”

Just be prepared to fall a few times, before discovering your north star. 

“The reality is, you will never get the business model or the specifics of the business right, right out of the gate,” he said. “It’s always failing your way to success.”