Warren Buffett may be a master of the stock market at 95, but even a lifetime of winning hasn’t shielded him from a deeply personal loss. He has said the biggest mistake of his life had nothing to do with money — it was not fully understanding the person who mattered most, his first wife, Susan Buffett.
In the HBO documentary “Becoming Warren Buffett” from 2017, Buffett reflected on how unbalanced he was early in life and how much of that changed because of her.
The woman who reshaped a “lopsided” life
“I just got very, very, very lucky,” Buffett said. “But I was a lopsided person, and it took a while. She just stood there with a little watering can and just nourished me along and changed me.”
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In the documentary, he pointed to struggles that had nothing to do with investing. Public speaking, for one, was something he couldn’t handle.
“I had been terrified of public speaking. I couldn’t do it. I’d throw up,” he said. “And I knew if I didn’t cure it then, I’d never cure it.”
That pushed him to take a Dale Carnegie course, which he credited as life-changing.
“If I hadn’t done that, my whole life would have been different,” Buffett said.
Even then, he made it clear Susan operated on a different level.
“She was 19 when we got married. I was 21. But she was so much more mature than I was. There’s no comparison,” he said. “She was a better person than I was.”
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The separation that didn’t end the marriage
The documentary then moves into a more complicated chapter. In 1977, Susan left Omaha to pursue her own life, but the marriage didn’t end. They remained close, stayed legally married, and continued to speak often despite living apart.
“She left Omaha in 1977, and really there isn’t much to say about that,” Buffett said in the film.
What he glossed over, others filled in. Their daughter, Susie, described what it looked like from the outside.
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“It was devastating for him,” she said.
Her concern wasn’t anger — it was that he wouldn’t be able to function on his own. That concern ended up shaping what happened next.
Before leaving, Susan asked friends to check in on him. One of them was Astrid Menks, a woman who would quietly become a central part of his life.
Menks eventually moved in, and over time, the relationship evolved into something unconventional but stable. Buffett remained married to Susan until her death in 2004, and two years later, he married Menks.
The mistake Buffett said mattered most
Looking back in the documentary, Buffett connected that entire chapter to a broader realization.
“Worst mistakes involve not understanding other people as well as you might,” he said.
It’s a striking admission from someone known for precision and discipline in business. In the film, he acknowledged that understanding people did not come as naturally.
Susan shaped who he became, but her leaving forced him to confront what he hadn’t fully grasped while she was there. The relationship didn’t collapse in a traditional sense — it evolved — but the lesson stayed.
For a man who built his reputation on recognizing value, Buffett has made it clear that one of his biggest blind spots wasn’t in the market. It was in understanding someone he already had.
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This article Warren Buffett Said First Wife Was a 'Better Person' Than Him — Losing Her Taught Him The 'Worst Mistake' Is Not Understanding People Better originally appeared on Benzinga.com
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