The worst investment Warren Buffett ever made was a textile company in New Bedford, Massachusetts. He bought it because it was cheap — the stock traded below the value of the inventory and machinery sitting on the factory floor. By the arithmetic he had been taught, it was a gift. You could buy the whole company for less than you could get by liquidating it. So he bought, and kept buying, and eventually took control.
The company was Berkshire Hathaway. The textile operation lost money for two decades before he finally shut it down. Buffett has said that anchoring his holding company to a dying mill cost him something on the order of $200 billion in compounded opportunity. He walked a road that had produced real fortunes, with total confidence, straight into a trap. The interesting question is not how a smart man made a dumb purchase. It is why the smartest investor alive needed almost ten years to stop.
The road that worked
The road belonged to Benjamin Graham, Buffett's professor at Columbia and the author of Security Analysis and The Intelligent Investor. Graham's signature technique was the "net-net": find a company whose stock trades below its net current asset value — cash and receivables and inventory, minus all liabilities, with the factories and brand thrown in for free. Buy a basket of them. Sell when they recover to fair value. Repeat.
It was almost purely mechanical. You did not need an opinion about the management, the industry, or the future of the product. You needed an annual report and the discipline to act on the numbers. Graham distrusted judgment about businesses precisely because judgment is where people fool themselves. The margin of safety lived in the price, not in the story.
This worked because of when it worked. From the wreckage of 1929 through the mid-1950s, the American stock market was a graveyard of overlooked companies. A generation had been burned and stayed away. Information moved by mail and ticker tape. There were few professional analysts and almost no institutional competition. Solid, profitable companies routinely traded for less than the cash in their bank accounts because nobody was looking. Graham's method was not a clever trick against an efficient market. It was a reliable machine for harvesting a market that was systematically, structurally cheap.
The conditions that changed
By the mid-1960s the terrain had moved under the road. Pension funds and mutual funds poured money into equities. The Chartered Financial Analyst program began credentialing armies of people doing exactly what Graham described. Brokerage costs fell, corporate disclosure improved, and information that once took weeks to surface now took days. The obvious bargains got found and bid up. The graveyard had become a crowded auction house.
Graham himself saw it. By the early 1970s he was telling interviewers that he no longer advocated elaborate security analysis to find superior opportunities — the field had grown too efficient for the edge that had defined his career to survive. The method was not wrong. It had simply been arbitraged into the ground. The road was still there, perfectly walkable. It just no longer led anywhere.
The road walks you into a wall
Berkshire Hathaway is the case study in what happens when you keep walking. Buffett bought it in the early 1960s on flawless Graham logic: a stock trading well below liquidation value. He was correct by every criterion he had been taught. He was also catastrophically wrong, because the criterion no longer matched reality. American textiles were being destroyed by foreign competition, and no discount to book value could fix a business whose end product had no future. Cheapness was a measure of the past, not a forecast of the future.
What is striking is how long he stayed. He poured capital into a mill he knew was failing, chasing the next quarter's marginal profit, unable to take the loss and walk away. The numbers that had justified the purchase had also become a justification for not selling. He was attached not just to the asset but to the road that had validated his entire identity as an investor.
The first step off
The departure has a date: 1972, and a product: See's Candies. Buffett's partner Charlie Munger pushed the deal hard, against Buffett's instincts. See's was not cheap. It sold for around $25 million, roughly three times book value — a price that would have made Graham close the file immediately. There was no margin of safety in the assets. The entire value sat in something Graham's framework could not even represent: a brand customers loved and would pay more for every year, a business that could raise prices without losing a single buyer.
Munger's insight was not a new valuation formula. It was the recognition that the source of return had moved. When markets were inefficient, the edge lived in price — buy the dollar for fifty cents. When markets grew efficient, price-based edges evaporated and the durable edge shifted to quality: a moat, pricing power, returns on capital that compound for decades. See's returned well over $2 billion on that $25 million over the next fifty years, almost none of it from the assets on the original balance sheet. Munger compressed the whole shift into one sentence: it is far better to buy a wonderful company at a fair price than a fair company at a wonderful price.
He knew, and still couldn't act
Here is the part that resists a flattering reading. Buffett was not blind to any of this. In 1964, years before See's, he had bought American Express during the Salad Oil Scandal — a wonderful business priced low only because of a temporary, recoverable crisis. That is not a Graham net-net. That is a quality bet on a franchise, and it worked spectacularly. The seed of the entire later philosophy was already in his hands.
And then he reverted. For years afterward he went back to Graham orthodoxy, kept hunting net-nets, and let Berkshire's mill bleed. He had seen the better road with his own eyes and still walked the old one. The obstacle was never a lack of intelligence or information. It was that the old road had worked too well. It had made him rich, made him respected, made him Buffett. You do not easily abandon the path that gave you everything you have, even when you can see, clearly, that it has stopped going anywhere.
The close
The decade from roughly 1965 to 1975 is the real story of Berkshire Hathaway, and it is not a story about genius. Buffett even wound down his investment partnership in 1969, telling his partners he could no longer find enough opportunities of the kind he knew how to evaluate — the road had stopped producing, and he still could not fully let go of it. What finally moved him was not a new idea arriving but an old idea dying slowly enough that he could no longer pretend otherwise, with Munger standing next to him naming it out loud.
The structural lesson is colder than the usual Buffett hagiography allows. Failure is a poor teacher's least dangerous student, because failure ends the lesson fast — you stop doing what does not work. It is success that builds the trap. Success constructs a road, paves it, names it after you, and convinces you that the road is the reason for the destination rather than the conditions you happened to walk it in. The conditions expire silently. The road remains, and you keep walking, because the most dangerous path you will ever be on is the one that worked.