Lee Su-jin cleaned love hotel rooms at 23 and is worth $1.6 billion at 48

Lee Su-jin took a job cleaning rooms in a South Korean love hotel at 23. He is now worth about $1.6 billion.

The Yanolja founder lost his parents young and spent his childhood moving between relatives, arriving at adulthood with no money and no particular plan. Love hotels, the short-stay motels catering to couples, carried enough social stigma in South Korea that people did not readily admit to working in one.

He was paying attention while he worked there. Lee watched how guests moved through the buildings, what frustrated them and what they could not find, and he founded Yanolja in 2007 to book exactly the kind of accommodation he had been cleaning. The name means roughly "hey, let's play."

The business worked by making a stigmatised category respectable. Yanolja emphasised safety, cleanliness and price, and grew as South Korean attitudes toward short-stay accommodation softened and travel booking moved online.

Lee bought aggressively as it scaled. Yanolja acquired the reservation service Hotel Now and the leisure business Leisure Q in 2016, then the e-commerce company Interpark in 2022.

It reached a billion-dollar valuation in 2019, becoming South Korea's eighth technology unicorn. SoftBank's Vision Fund 2 arrived two years later with an investment that valued the company at $6.7 billion, one of the largest single commitments to a South Korean startup on record, and brought Singapore's sovereign fund GIC in alongside it.

The part of the business Lee treats as the moat is software rather than bookings. Yanolja Cloud sells hospitality management systems to tens of thousands of hotels worldwide, handling reservations, operations and guest services. The consumer app has been downloaded more than 57 million times, and the combined NOL Universe platform serves about 13 million monthly active users.

Forbes attributes his operating style to where he started, describing an instinct to act rather than wait for conditions to improve. He moved into new categories, countries and technologies before competitors had decided they mattered.

The flotation everyone expected after SoftBank invested has not happened. Yanolja has said repeatedly it is in no hurry, preferring to build before submitting to public market scrutiny.

Lee owns close to a third of the company alongside his wife and two daughters, and Forbes ranks him 18th among South Korean billionaires. His arrival on the Forbes Korea 50 Richest list marked the point at which a janitor from the least respectable corner of the hospitality industry was counted among the country's significant businessmen.