Payal Kadakia doesn’t have to sweat over achieving success — it's already hers.

Kadakia, 35, is the co-founder of ClassPass, the subscription-based service that lets users find and book fitness classes online. Despite her young age, she already boasts an impressive number of business accolades.

After four years at the company's helm, Kadakia stepped down as ClassPass CEO in March 2017. She currently serves as executive chairman of the company, which launched in 2013 and has raised a total of $173 million from outside investors to date, bringing its valuation to a hefty $470 million. Meanwhile, Forbes pegged Kadakia’s net worth to be at least $50 million in 2016, a year in which she landed spots on both Forbes’ Women Entrepreneurs to Watch list and Fortune’s 40 under 40.

Kadakia — who clearly knows a thing or two about success — recently shared with CNBC Make It what she believes the biggest difference between successful and unsuccessful people boils down to: execution.

“Ideas are a dime a dozen, and people can have ideas, but you need to be able to get stuff done,” Kadakia says. “And I really think it’s the people who know how to work — and whether that’s the big, higher-level stuff and also the nitty-gritty — they know how to get in there and get their hands dirty and solve problems.”

That type of hard work is something that Kadakia learned early on, well before she became an entrepreneur. Her mother, an immigrant from western India, came to the U.S. in the 1970s. Her work ethic had a long-lasting impact on Kadakia, who credits her drive to "watching my parents go from this life where they had to build everything and start a whole new life here. And I think watching their experience and how hard they worked taught me that."

Kadakia, who also serves as the artistic director for The Sa Dance Company, an Indian-American dance troupe, adds that the discipline she learned as a dancer growing up also taught her a lot about putting in hard work.

“I think the dance side of my life, which has always been sort of there since I was really young, just taught me if I had a vision to do something, okay, I’m going to work hard and keep practicing, keep rehearsing. And if I put the work in, the output will come,” Kadakia says.

ClassPass has had its shares of hills and valleys over the past few years. The company's growing pains included discontinuing its popular “unlimited” classes offering and hiking prices in 2017 as part of a revamped business plan aimed at boosting the company's profits. The changes brought some backlash from customers. But the new business model also helped the company attract its latest round of outside funding, $70 million in June 2017. The company said in May it will use this new infusion to expand internationally, adding locations in nine new countries by the end of 2018.

ClassPass’s network now includes 10,000 fitness studio partners, with members in 50 cities across the U.S., U.K. and Canada who have booked roughly 50 million reservations for fitness classes since the company launched five years ago.

To get through tough times, Kadakia says she focused on that vision and the overall impact ClassPass was having on people’s lives. “In the beginning, when we went through the ups and downs that we went through, the thing in my head was that reservation number,” Kadakia explains. “Because without that, I wasn’t impacting people’s life and time.”

As a founder, she says it also helps to find a purpose behind your passion. ClassPass’s vision statement is “every life fully filled." What the company means by that, Kadakia explains, is that it wants “people’s time to be spent as nurturing and as inspiring as possible.”

“I think it’s important for founders to be very tied to their mission," she says. "Start a product at a company that you’re willing to work on for decades. To solve problems takes time, and it’s going to be a hard journey and there’s ups and downs.”

"If the passion is not there," she says, "you’re just never going to get over those humps, because you’ll never have the fuel to get through it."

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