‘The worst mistakes are the ones you don’t see..’: Warren Buffett on his biggest investing regret

An old video clip of Warren Buffett has resurfaced on social media platform X, reigniting debate around one of investing’s most uncomfortable truths: even the greatest investors make mistakes. The clip, recently shared by an X user Sunil Gurjar, shows Warren Buffett reflecting candidly on what he calls the worst kind of investment error—not losses that appear on balance sheets, but opportunities that were never taken.

Known globally as the “Oracle of Omaha,” Buffett is the long-time chairman and chief executive of Berkshire Hathaway, a company he transformed from a struggling textile business into one of the world’s most valuable conglomerates. With a net worth of over $130 billion, Buffett ranks among the richest individuals globally, yet his enduring appeal lies in his humility and long-term approach rather than sheer wealth.

The mistake Buffett says hurts the most

In the widely circulated clip, Buffett makes a clear distinction between losses that investors can see and those they often overlook. “Oh, I made some very bad ones but that doesn’t really bother me. It bothered the shareholders,” Buffett says in the video. He goes on to explain that mistakes are inevitable in both life and investing, but the real danger lies elsewhere. “The biggest mistakes are the mistakes that don’t show up. Mistakes of omission, rather than commission,” he adds.

Buffett reveals that while Berkshire Hathaway has never lost an extraordinary amount of money on a single investment, the company has missed out on massive gains by not acting when it had the chance. “We have missed profits of as much as maybe $10 billion in things that I knew enough to do and I didn’t do,” Buffett says, underlining how inaction can sometimes be more costly than a wrong decision.

This philosophy is deeply rooted in Buffett’s broader investment framework. He is known for focusing on businesses with strong fundamentals, durable competitive advantages, capable management, and long-term growth potential. At the same time, he has repeatedly warned investors against overtrading, chasing trends, or reacting emotionally to short-term market movements.

Buffett’s famous investing quotes—such as “be fearful when others are greedy and greedy when others are fearful”—have shaped generations of investors. His emphasis on patience, discipline and understanding businesses before buying their stocks stands in stark contrast to today’s fast-paced trading culture.

The renewed attention to this old video comes at a time when markets are increasingly driven by speculation and short-term narratives. Buffett’s remarks serve as a reminder that even legendary investors accept mistakes as part of the journey, but strive to avoid the ones that quietly compound over time.

For retail investors, the lesson is simple yet powerful: losses can often be recovered, but missed opportunities—when conviction meets inaction—can carry a far heavier long-term cost.

Disclaimer: The views and recommendations made above are those of individual analysts or broking companies, and not of Mint. We advise investors to check with certified experts before making any investment decisions.