Yanolja founder and chairman Lee Su-jin started his lucrative career in the travel industry as a motel janitor.

The experience inspired him to launch hotel booking site Yanolja, which is Korean for "Hey, let's play," in 2007. Now also a popular travel app, the brand's become a global phenomenon with over 57 million downloads, according to its website.

Its success helped Lee build his own fortune, too. He now has a net worth of $1.2 billion, which comes from owning nearly a third of Yanolja with his wife and two daughters, according to Forbes. He made his debut in the publication's Korea's 50 Richest rankings this spring.

But Yanolja was born out of necessity, rather than a love of travel. Lee was orphaned at a young age, and stayed with family members for most of his childhood, according to Bloomberg. When Lee was 23, he cleaned rooms at a "love hotel" — a type of motel known for offering short-term accommodations at an hourly rate — in exchange for a steady paycheck and a place to stay.

"Day in and day out, I felt wretched but hung on," Lee, now 45, told Bloomberg in 2017. "It feels like a dream now."

He saved his money, invested in stocks and even started a salad business, according to Bloomberg. When that company failed, he pivoted back to hospitality — and at an opportune moment.

Given their affordability, love hotels were typecast as safe havens for sex workers in the early 2000s, and those stigmas were bad for business, Yanolja's CEO Kim Jong-yoon told CNBC Make It in 2019. When South Korea passed an anti-prostitution law in 2004, Lee worried the motels that gave him security would go under.

So he decided to rebrand love hotels. He created a hotel review platform in 2005, which became Yanolja two years later. His goal was to modernize the hotels, and convince young couples and travelers they were safe, convenient and cost-effective.

"If all the motels relied on love, they'd starve to death," Lee told Bloomberg.

Kim said Lee's janitorial job, where he could observe guests' experiences in love hotels, was actually a benefit: It gave him a leg up in tailoring the platform to its consumers.  

"I think such kind of experience is very, very helpful to understand the nature of the industry," Kim said.

In June 2019, Yanolja become South Korea's eighth "unicorn" startup by achieving a valuation of more than $1 billion during a funding round.

Two years later, investment company SoftBank Vision Fund 2 bought a minority stake in Yanolja for $1.7 billion at a $6.7 billion valuation, according to Forbes.

The deal with SoftBank sparked widespread speculation of a potential initial public offering for Yanolja. However, the company has yet to go public, and Kim even said in a July 2022 press release that Yanolja was in no rush to announce an IPO with the hospitality industry still recovering from the height of the Covid-19 pandemic.

The company has expanded well beyond travel booking, having launched Yanolja Cloud, its own artificial intelligence software for other hospitality and leisure platforms, in 2021. Now, 19 million combined users make use of Yanolja's software platforms for booking, travel and property management operations, according to the company's website.

That reach is something to be proud of, Kim told Reuters in 2019, but the company also achieved Lee's goal of shifting the culture and perception of love hotels.

"Previously, many people were not able to go to motels out of embarrassment," Kim said. "But we've drawn in guests even for travel. That's the biggest change."

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