There seems to be no shortage of people eager to meet Warren Buffett. 

Every year, investors flock to the annual meeting of Berkshire Hathaway, the billionaire investor's holding company, to catch a glimpse of Buffett and possibly ask him a question. And the annual charity auction for a lunch with Buffett now regularly fields multi-million dollar bids (this year's winner paid nearly $4.6 million, even if he did postpone at the last minute).

And yet, fellow billionaire Bill Gates says he wasn't even sure he wanted to meet Buffett at all before the two iconic businessmen finally crossed paths in the early 1990s. In an interview at The New York Times/DealBook conference on Wednesday, the Microsoft co-founder explained why he was initially reluctant to meet with Buffett.

"I didn't even want to meet Warren because I thought, 'Hey this guy buys and sells things, and so he found imperfections in terms of markets, that's not value added to society, that's a zero-sum game that is almost parasitic.' That was my view before I met him … he wasn't going to tell me about inventing something," Gates said at the conference.

Gates simply felt that he and Buffett operated too differently in the world of business for there to be any value in them meeting and sharing insights — Buffett is an investor looking to create value for himself and his shareholders, while Gates, especially at that point in Microsoft's history, was more focused on building software that would change the way people and businesses use computers in their daily lives. (His company released its first Microsoft Office suite and Windows 3.0 in 1990, a year before Gates and Buffett actually did meet).

Despite his reluctance, Gates did eventually meet Buffett when the tech billionaire's parents invited Buffett to dinner during a visit to Washington state in July 1991. As Gates has said in the past, he actually tried to get out of attending the dinner, telling his mother, "'Mom, I'm busy!'"

Gates finally agreed to spend no more than a couple of hours at the dinner with Buffett before returning to work. But once the two men met, Gates said Buffett amazed him by pressing him with "amazingly good questions that nobody had ever asked," Gates wrote in a 2016 blog post that reflected on his eventual decades-long friendship with the investor.

Their dinner conversation was enough to convince Gates that Buffett had plenty to offer. "I realize everything he does is based on a framework of the world where he's judging — judging markets, judging people, judging how things work, in a very deep way," Gates said at the DealBook conference. "I realized [that] although we come from different places, we're both trying to model the world and what goes on."

Buffett "didn't come across as a big shot investor" during a dinner conversation that went on for "hours and hours," Gates wrote in 2016. "[Buffett] had this modest way of talking about what he does. He was funny, but what impressed me most was how clearly he thought about the world."

That meeting sparked what has now been a nearly three-decade friendship between the two billionaires. (Gates is the world's second-wealthiest person, with a net worth of $109 billion, with Buffett's $87.8 billion net worth ranking fourth in the world, according to Bloomberg.)

"[The dinner] began a really unbelievable friendship for me and I could tell that even though we came from different directions, the kinds of things that fascinated us and that we thought were important were very much the same," Gates told business students at the University of Nebraska in 2006.

In addition to their friendship, Gates and Buffett joined forces in 2010 to announce The Giving Pledge campaign, through which the pair have recruited over 200 wealthy people around the world to donate the bulk of their fortunes to philanthropic causes. 

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