At PandoMonthly in San Francisco, Reid Hoffman tells Sarah Lacy he didn’t understand the potential of Twitter early enough to become an investor, and it’s one of his biggest regrets.

“When I initially heard about Twitter, I thought, why are people motivated…to do the status update,” says Hoffman. “By the time I got it, so had a bunch of other people and it was past my angel investing criteria.”

Hoffman’s “PayPal Mafia” friend Peter Thiel famously dismissed Twitter saying, “We wanted flying cars, instead we got 140 characters,” but Hoffman disagrees, saying it will be an “ecosystem foundation” of the web.

“It’s a public sphere of attention gestures that’s actually really useful,” says Hoffman.

Watch more of Sarah’s conversation with Hoffman on PandoDaily’s YouTube channel.