Elon Musk said he isn't the 'biggest fan' of Warren Buffett. The billionaires have butted heads before.

• Elon Musk revealed he isn't the "biggest fan" of Warren Buffett on "The Joe Rogan Experience" podcast last week.
• The Tesla and SpaceX CEO said the famed investor and Berkshire Hathaway boss has "kind of a boring job."
• The pair have butted heads before: Buffett said he wouldn't invest in Tesla in March, and said Musk's behavior as a CEO had "room for improvement" last year.
• "Elon may turn things upside down in some areas. I don't think he'd want to take us on in candy," Buffett said in 2018.
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Elon Musk delivered his most direct criticism of Warren Buffett yet on "The Joe Rogan Experience" podcast last week, revealing he isn't a huge admirer of the famed investor and Berkshire Hathaway boss.

"To be totally frank I'm not his biggest fan," the Tesla and SpaceX chief said in a discussion of the ongoing backlash against billionaires. Musk drew a distinction between consumption and Buffett's focus on allocating funds among different businesses.

"He's trying to figure out: 'Does Coke or Pepsi deserve more capital?'" Musk said. "It's kind of a boring job if you ask me."

Musk's comments came after Buffett acknowledged the billionaire entrepreneur has "done some remarkable things" during a Yahoo Finance interview in March, but dismissed the notion that he would invest in Tesla.

Buffett struck a similar chord in a Yahoo Finance interview in April 2019. He described Musk as a "remarkable guy" but questioned Musk's behavior as CEO, specifically his Twitter habit.

"I think he has room for improvement, and he would say the same thing," Buffett said. "Some people have a talent for interesting quotes and others have a little bit more of a blocker up there."

The pair's most famous clash was over Buffett's concept of "economic moats," or enduring competitive advantages such as a powerful brand or patented technology.

Musk dismissed the idea on a Tesla earnings call in May 2018, saying "moats are lame." Buffett countered at Berkshire's shareholder meeting a few days later.

"Elon may turn things upside down in some areas. I don't think he'd want to take us on in candy," he said, referring to Berkshire-owned See's Candies, his "dream business."

"I'm starting a candy company [and] it's going to be amazing," Musk tweeted in response.