Amazon hitting $1 trillion market cap is just the latest milestone this year for Jeff Bezos

Amazon market cap hit $1 trillion on Tuesday, making it the second publicly traded U.S. company to reach the record valuation, just more than one month after Apple hit the milestone.

It's the latest achievement in a landmark year for Amazon founder and CEO Jeff Bezos.

Earlier in 2018, Bezos became the richest person alive. His net worth now totals $166.5 billion, according to Forbes' billionaires list. Going by Forbes' calculations, Bezos is worth roughly twice as much as tech leader Bill Gates and the 'Oracle of Omaha' Warren Buffett.

This May, Amazon cracked the top 10 of the Fortune 500 list, alongside corporate behemoths Apple, Berkshire Hathaway, Exxon Mobil and, of course, Walmart.

With revenue of $177.87 billion, as of the company's 2017 fourth-quarter earnings report, Amazon placed eighth on this year's Fortune list of America's largest companies. That's up four spots from its rank last year as No. 12. Amazon made its debut at No. 492 on the Fortune 500 back in 2002, the same year its biggest competitor Walmart first landed in the No. 1 spot. Amazon has since quickly gained on, and nearly caught up with, Walmart.

Amazon's customer base has remained loyal through the latest Prime price hike in exchange for a slew of services and perks, and the company's stock has continued to increase in value. Even Buffett now regrets not investing in Amazon when he had the chance.

"What Jeff Bezos has done and is likely to do is perhaps the most remarkable achievement I've seen," Warren Buffett reportedly told Forbes editor Randall Lane. "Because he's taken two very major industries, and simultaneously, and sort of under the nose of competitors, he's become in effect the leader and is redefining them and succeeding at really big businesses."

Bezos' success can arguably be traced back to a risk he took when he was 30 years old. While serving as a vice president at the hedge fund D. E. Shaw in the 1990s that Bezos came up with the idea to sell books over the Internet. Doing so, however, would mean taking a significant risk and perhaps sacrificing his stable job.

"I came across the fact that Web usage was growing at 2,300 percent per year," Bezos said in a 2010 address at his alma mater. "I'd never seen or heard of anything that grew that fast, and the idea of building an online bookstore with millions of titles — something that simply couldn't exist in the physical world — was very exciting to me."

At the 2017 Summit LA conference, Bezos recalled that, when he told his boss about his Internet bookstore idea, his boss said, "I think this is a good idea, but I think this would be an even better idea for somebody that didn't already have a good job."

That's when Bezos considered what his 80-year-old self would say if he didn't seize this opportunity.

"In most cases, our biggest regrets turn out to be acts of omission. It's paths not taken and they haunt us. We wonder what would have happened," Bezos said at Summit LA. "I knew that, when I'm 80, I would never regret trying this thing that I was super excited about and it failing. If it failed, fine. I would be very proud of the fact when I'm 80 that I tried. I also knew that it would always haunt me if I didn't try."

After "a lot of soul-searching," Bezos quit his job to start his dream company in 1994 and the decision paid off: Amazon went public three years later.

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This is an updated version of a previously published article.