hedge fund manager Bill Ackman spends a lot of time learning from his mistakes and in a recent interview he spoke about how his bets have served as learning opportunities.

Reliving the Gotham Days: There may not be a formal autopsy after a debacle, but many lessons have certainly been learned, Ackman said on a 20VC podcast published earlier this week.

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The fund manager determined when Gotham Partners, his first fund, collapsed, he learned some pretty valuable lessons. Tracing Gotham’s origins, he said it began investing in liquid public securities and then received a mandate from investors to invest.

“The asset-liability mismatch caused us to withdraw,” he said.

“The lesson from the Gotham experience was the importance of liquidity, you shouldn’t have an open-end fund, like a hedge fund, where people can redeem capital and it’s liquid assets.”

It was then that Pershing Square Capital Management was set up to only invest in liquid, large-cap stock companies, he said, adding, “It’s served us really well.”

“I always like to say that experience is about making mistakes and learning from them. I spend a lot of time learning from mistakes,” Ackman said.

Missed Opportunities: Ackman also said his firm will not only talk about securities they’ve bought that have fallen in value, but also missed opportunities.

“We talk just as much about a missed opportunity, a situation where, given our knowledge, experience, expertise, etc., we should have taken advantage and made a fortune, and maybe only made a small fortune or we didn’t make anything because we didn’t do it,” he said.

Miss alphabet inc Google GOOD can be an equally important mistake, or perhaps even a bigger mistake, the fund manager said.

Last mess: Ackman said the last mess discussed as a team at Pershing was Netflix Inc. NFLX. He noted that Pershing Square took a billion dollar position in streaming…