Laura BeckSat, Jun 21, 2025, 4:01 PM 6 min readWarren Buffett didn’t build his more than $100 billion fortune by being perfect. In fact, the Oracle of Omaha has been surprisingly candid about his biggest financial flubs over the decades. The good news is his mistakes offer valuable lessons for anyone trying to build real, sustainable wealth. Plus, they prove that even legendary investors are just humans who get it wrong sometimes. Welcome to the club!Find Out: 10 Genius Things Warren Buffett Says To Do With Your MoneyRead Next: Clever Ways To Save Money That Actually Work in 2025Here are Buffett’s top money mistakes and, more importantly, what he learned from them.Buffett’s investment in U.K. grocer Tesco shows how hesitation can turn small problems into major losses. Berkshire owned 415 million shares by 2012, but when concerns about management surfaced, Buffett sold only part of his position for a $43 million profit.When Tesco later overstated profits and shares collapsed, his delayed action cost Berkshire $444 million in after-tax losses. “An attentive investor, I’m embarrassed to report, would have sold Tesco shares earlier. I made a big mistake with this investment by dawdling,” Buffett said.Speed matters in damage control. When red flags are abundant, sometimes quick decisive action means you avert a financial disaster.Learn More: Warren Buffett Offers One Piece of Estate Planning Advice to the Middle ClassBelieve it or not, Buffett has called Berkshire Hathaway “the dumbest stock I ever bought.” He purchased what was, at the time, a failing textile company because he felt insulted during a sale negotiation. Instead of walking away from Berkshire Hathaway as planned, his wounded pride led him to buy the entire business and fire the previous owner.The financial cost was enormous. Buffett said his holding company would be “worth twice as much as it is now” if he’d stuck to his original plan of investing in insurance companies instead. This single emotional reaction cost him decades of better returns.The takeaway is clear: Never let personal feelings influence money decisions. When you feel personally slighted in a financial deal, that’s exactly when you need to step back, take a breath and think logically.In 1993, Buffett thought Dexter Shoes had lasting competitive advantages that would protect its profits. Within a few years, those advantages evaporated and the company became worthless.Buffett explained: “What I had assessed as a durable competitive advantage vanished within a few years.”Terms and Privacy PolicyPrivacy & Cookie SettingsMore InfoS&P Futures5,993.50 -24.50 (-0.41%)Dow Futures42,343.00 -172.00 (-0.40%)Nasdaq Futures21,726.75 -118.00 (-0.54%)Russell 2000 Futures2,114.80 -10.10 (-0.48%)VIX20.62 -1.55 (-6.99%)Gold3,371.90 -13.80 (-0.41%)PortfolioSign in to access your portfolioSign inTop gainersGMS GMS Inc. 100.27 +19.26 (+23.77%)UAA Under Armour, Inc. 7.03 +0.86 (+13.94%)OSCR Oscar Health, Inc. 21.22 +2.45 (+13.05%)WLYB John Wiley & Sons, Inc. 45.41 +5.16 (+12.82%)ZETA Zeta Global Holdings Corp. 14.18 +1.59 (+12.63%)Top losersLYEL Lyell Immunopharma, Inc. 8.69 -0.89 (-9.29%)CSAN Cosan S.A. 5.28 -0.50 (-8.65%)HCC Warrior Met Coal, Inc. 43.18 -3.83 (-8.15%)KBR KBR, Inc. 48.93 -3.85 (-7.29%)ACN Accenture plc 285.37 -21.01 (-6.86%)Most activeNVDA NVIDIA Corporation 143.85 -1.63 (-1.12%)INTC Intel Corporation 21.08 -0.41 (-1.91%)AMCR Amcor plc 8.97 -0.08 (-0.88%)LCID Lucid Group, Inc. 2.1900 -0.0300 (-1.35%)F Ford Motor Company 10.59 +0.16 (+1.53%)Earnings eventsTrending tickersCL=F Crude Oil Jul 25 75.43 +1.59 (+2.15%)NQ=F Nasdaq 100 Jun 25 21,726.75 -118.00 (-0.54%)BTC-USD Bitcoin USD 101,133.82 -1,287.63 (-1.26%)ES=F E-Mini S&P 500 Sep 25 5,993.50 -24.50 (-0.41%)YM=F Mini Dow Jones Indus.-$5 Sep 25 42,343.00 -172.00 (-0.40%)Top economic eventsPowered by Money.com - Yahoo may earn commission from the links above.