Warren Buffett thinks every entrepreneur needs to do this

If you're an aspiring entrepreneur or small business owner, Warren Buffett wants you to do something tomorrow morning.

"Tomorrow morning, when you look in the mirror after you've gotten up, just write — put it in lipstick or whatever you want on the mirror — just put 'delight my customer,'" Buffett said at Goldman Sachs (GS)' 10,000 Small Businesses panel event at LaGuardia Community College on Tuesday afternoon.

The phrase is not "satisfy my customer," Buffett clarified.

Since happy customers are your best advocates, "any business that has delighted customers has a salesforce out there," the chairman and CEO of Berkshire Hathaway (BRK-A) said. "You don't have to pay them, you don't see them, but they're talking to people all the time."

Buffett shared a personal anecdote about buying a car approximately one year ago.

"I don't remember how much I paid, but I remember the experience I had," he said, adding that most customers think the same way.

"Your customer is going to get to vote and talk, and you want them out there as salesmen for you," Buffett said.

In fact, customer delight is the main ingredient for success, Buffett said.

"You will succeed if you have delighted customers," he said. "Don't settle for satisfied."

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