He has a net worth of $3.3 billion, and a track record that includes co-founding PayPal and LinkedIn.

But for all his massive success, Reid Hoffman says there's one big regret he has about the professional decisions he's made.

Here's a quick look at his best choices, the one regret he talked about, and how you can avoid making it in your own career and life.

"The entire trajectory of my life"

The best career decision Hoffman says he ever made, according to The Wall Street Journal, was to accept Peter Thiel's invitation to join the board of Confinity, which ultimately launched PayPal.

He did so, even though he originally thought the company had "a terrible idea," Hoffman said, because he realized Thiel and his team were brilliant. Taking the risk changed everything for him.

"The entire trajectory of my life, and my impact in the world and my impact in the Valley would be different without having made that bet," he said.

Now an investor at Greylock Partners, Hoffman, according to the Journal, is "generally considered one of Silicon Valley's most-high-profile angel investors," and he gets pitched constantly: between 100 and 200 pitches a week. He winds up taking maybe six or eight of them seriously.

And it's what he did with one of those six serious weekly pitches that led to his single biggest regret, he said.

Airbnb, Facebook--and Stripe

Things often work out big time for Hoffman as an investor.

He got in early at Airbnb, and he also put up $37,500 very early in Facebook, even though a teenaged Mark Zuckerberg told him he wasn't even sure he was going to leave Harvard at the time. Hoffman's relatively small investment was ultimately worth $400 million.

But, according to the Journal, there's one big opportunity he had that he let slip through his fingers, and that ranks now as his biggest professional regret.

It's that he turned down the chance to have been an early investor in the online payments company Stripe, founded by brothers and Y Combinator alumni Patrick and John Collison:

Mr. Hoffman met the brothers, liked them, and acknowledged that they had a "really good" idea. But he passed, because he thought they were valuing Stripe too high, and because he knew just how hard it is to make a go of it as a payments company.

Stripe is now valued at more than $9 billion, according to news reports on funding rounds. By passing on the opportunity, Mr. Hoffman missed out on millions.

"Losing those is the thing that is the disaster. It's the, 'Oh, my God! This thing is going to the moon and I'm not in it!'" Hoffman later said.

Planning your regrets

I admit when I first read these remarks, my reaction was along the lines of: Really? You're worth $3.3 billion. Your biggest professional regret is not having made yet another successful early investment?

But shave off a zero or two, and it's really the same kind of choice that most of us face in our personal and professional lives. 

Do I take the risk? Or do I do the safe thing?

It brings to mind an ​apocryphal quote we've all heard, about how people don't regret the things they do by and large, but they regret the things they didn't do.

The choices they didn't make. The risks they didn't take.

Interestingly, it's a crutch that LinkedIn might actually facilitate. It's a lot easier to have a measure of success in your life and career by being fairly passive on LinkedIn: optimizing your profile, sitting back, waiting for opportunities to come to you.

Avoiding risk and big plays.

But take it from LinkedIn's lead founder himself: That's the wrong way to go about it. You might wind up successful, but you'll still have regrets.