Why Mavs owner Mark Cuban spent 30 minutes signing autographs for Boston fans

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Self-made billionaire Mark Cuban

Mark Cuban packs a lot into one day. The "Shark Tank" star, billionaire entrepreneur and father of three is also the owner of the Dallas Mavericks. But he still makes time for his fans.

After one NBA game at TD Garden in Boston, the self-made billionaire stuck around for more than 30 minutes to sign autographs, Salesforce's Vala Afshar pointed out on Twitter last week.

"I don't think he walked away from anyone who asked," Afshar tweeted. "I've been to a number games, and I don't recall seeing any other NBA team owner doing the same."

In a retweet, Cuban explained his logic for staying: "I know who pays our bills!"

The businessman has previously underlined the importance of connecting with the people you serve. As Cuban says he likes to remind himself every day, "Treat your customers like they own you. Because they do."

Start by putting yourself in their shoes, he says, and experiencing things from their point of view: "If I can't be a customer of my own product, then I probably am not doing a good job running the company."

In Cuban's case, that means watching the Mavericks play from a seat that is for sale to the general public. "I'm not surrounded by security. I don't get special anything," Cuban wrote on his blog in 2006. "If the Nachos are slow and the beer is warm, I know it and the people sitting around me also let me know."

Ultimately, to be successful in business, "you have to re-earn your customers business every day," says Cuban.

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