Not even a six-figure fine can get Mark Cuban to change his leadership tactics.

Shortly after Cuban became a billionaire, following the sale of his company Broadcast.com to Yahoo in 1999, he acquired a majority stake in the NBA's Dallas Mavericks for $285 million. A year later, he was fined $100,000 by the league for his unconventional methods of team leadership, he tells CNBC Make It.

At the time, Cuban was 41 and full of energy after buying his way into his dream job. Hoping to convey to his new employees that he wanted to engage with every part of the organization, he'd often sit on the floor, chatting with the equipment staffers who collected the players' sweaty jerseys, he recently told NBA player Draymond Green's podcast, "The Draymond Green Show."

"I'm sitting with those dudes because I want to get to know them better. I want to see their job and I want to be close to the team just to get a feel for the vibe," Cuban said. "And they fined me $100,000 ... for conduct unbecoming of an owner."

Cuban learned his approach — using his interpersonal skills to get his employees on the same page — the hard way. While running Broadcast.com, he was an overbearing boss who focused more on results than employee morale, he told Vanity Fair in 2018.

"I went through my own metamorphosis, if you will. Early on in my career," said Cuban. "I wouldn't have wanted to do business with me when I was in my 20s [and 30s]. So I had to change, and I did, and it really paid off."

The philosophy wasn't popular among the NBA's other team owners, including "the old dudes who inherited their teams [or] won them in a poker game or whatever," Cuban told Green's podcast. He stuck with his approach anyway, he added, telling then-NBA commissioner David Stern: "You ain't seen nothing yet."

The billionaire was publicly fined 20 times by the league, in total, before Stern retired in February 2014.

Cuban sold a majority of the Mavericks last year for $3.5 billion, retaining a 27% minority stake. He still leans on his interpersonal leadership approach today, often providing advice, building connections and offering mentorship to contestants on ABC's "Shark Tank."

If you're struggling with your own leadership style, Cuban recommends figuring out what being a leader actually means to you.

"Leadership to me is having a vision, what's my goal," he said in a 2022 discussion with the National Society of Leadership and Success. "Then, Part 2 is getting to know the people that are working with me and what their goals are. And then the real definition of leadership is making those two merge."

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

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