The day Mark Cuban became a millionaire, he took off his watch and threw it away—here’s why

Some people celebrate big career wins by splurging on a Rolex watch.

Not Mark Cuban. At age 32, he sold his first startup — a software company called MicroSolutions — for $6 million. That same day, he took off his watch and threw it away, he said at a SXSW panel earlier this month.

It was symbolic: After gaining that financial security, he didn’t want to feel like anyone owned his time, he said.

“Time is the one asset you can never get back. You can never truly own [it],” said Cuban, 65. “I wanted to be … in a position where I get to call my own shots [and] spend time the way I wanted to spend time. That was always my motivating factor.”

Cuban inherited that mantra at age 14 from his dad, who worked 60 hours per week for a company that upholstered cars outside of Pittsburgh, he told CNBC Make It last month. Sometimes, his dad brought him to work to show him what it looked like to work for someone else.

“This time wasn’t spent to learn about what my dad did, but to learn that his job didn’t have a future,” Cuban said. “His time was never his own … he wanted me to create my own path.”

When Cuban’s next company, audio streaming service Broadcast.com, sold to Yahoo for $5.7 billion in stock in 1999, he took a much larger step toward protecting his time: buying a private plane for $40 million.

The transaction is still the largest single e-commerce transaction in the Guinness Book of World Records. “[Buying a private plane] was my all-time goal because the asset I value the most is time, and that bought me time,” Cuban told told Money in 2017.

Today, Cuban wears an Apple Watch to track his health metrics, he said at SXSW — but it hasn’t changed his stance on time. He spends most of it either with his family, helping run the NBA’s Dallas Mavericks, appearing on ABC’s “Shark Tank” or running his pharmaceutical company, Cost Plus Drugs.

“I wanted to make enough money so I didn’t have to respond to anybody else,” Cuban said in a recently released MasterClass course. “I could make my own schedule and live my own life the way I wanted to do it.”

Disclosure: CNBC owns the exclusive off-network cable rights to “Shark Tank.”

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