The Amazing Thing About a 98% Error Rate

One of the most misunderstood realities in investing is that accuracy matters far less than most investors believe.

Human beings are naturally attracted to precision. We admire investors who appear capable of forecasting economic trends, predicting earnings surprises, timing recessions, and identifying winning stocks with remarkable consistency. Financial media reinforces this tendency every day by celebrating forecasts, quarterly predictions, and market calls.

Yet the historical record of wealth creation in public markets tells a very different story.

The greatest fortunes in investment history were often not built through extraordinary forecasting ability. They were built through identifying a small number of exceptional businesses and possessing the temperament to hold them while they compounded for decades.

This principle was highlighted brilliantly by Mohnish Pabrai during a recent discussion on The Investor’s Podcast. Pabrai proposed a fascinating thought experiment involving Walmart.

Imagine an investor allocated $100,000 across fifty stocks. Suppose only 2% of the portfolio was invested in Walmart. Suppose further that every other company in the portfolio went to zero. A catastrophic 98% failure rate.

A portfolio manager operating under modern institutional standards would almost certainly be fired. Financial media would describe the performance as a disaster. Risk committees would conclude the investment process was fundamentally flawed.

Yet the remarkable reality is that a single Walmart position held from the early 1970s until today would have generated returns so extraordinary that the investor would still have significantly outperformed the S&P 500.

The implications of this observation are profound. It challenges many deeply held assumptions about diversification, stock selection, portfolio construction, and what actually drives long-term investment success.

More importantly, it reveals why investing is simultaneously much simpler and much more psychologically difficult than most people imagine.

The Mathematics of Extreme Wealth Creation

Most investors think wealth creation resembles a normal distribution. They imagine that investment outcomes are spread relatively evenly across thousands of securities. Reality looks nothing like that.

Research examining nearly a century of stock market history consistently demonstrates that wealth creation is extraordinarily concentrated. A very small percentage of companies generate the overwhelming majority of aggregate stock market wealth.

The vast majority of publicly traded companies either underperform the market, match the market approximately, produce mediocre returns, or fail entirely. Only a tiny minority becomes transformational compounders — generating returns so extraordinary that they overwhelm the losses generated elsewhere.

This phenomenon is not unique to public equities. It appears repeatedly throughout economic history.

• In venture capital, a small handful of investments often produce nearly all fund returns.
• In private equity, a small number of deals drive overall performance.
• In entrepreneurship, a tiny fraction of businesses create most industry value.
• In innovation, a small handful of inventions reshape entire civilisations.
• Nature itself operates this way.

The distribution of outcomes is rarely normal. Instead, outcomes are dominated by extreme winners. Investing is no exception.

The practical implication is that investors should spend less time obsessing over avoiding every mistake and more time ensuring they do not miss the rare businesses capable of compounding capital for decades.

The Hidden Cost of Selling Winners

Most investors understand the danger of purchasing poor businesses. Far fewer understand the danger of selling exceptional businesses. Ironically, the latter mistake is often much more costly.

Consider some of the greatest compounders in modern market history: Microsoft, Apple, Amazon, Costco Wholesale, Berkshire Hathaway, and Tencent Holdings.

The overwhelming majority of investors who owned these companies never captured their full returns. They sold after a doubling, a tripling, a five-fold increase, or a tenfold increase. The position became “too large.” Valuation appeared “too expensive.” The gains felt “too good to lose.” Portfolio theory demanded rebalancing.

Yet extraordinary wealth is often created only after the first ten-fold increase. The difference between a 10-bagger and a 100-bagger is not merely quantitative. It is transformational.

The biggest mistake many investors make is not buying bad businesses. It is interrupting the compounding process of great businesses.

Warren Buffett’s Greatest Lesson

The investing world often associates Warren Buffett with value investing. That description is accurate but incomplete. Buffett’s greatest contribution may be demonstrating the power of prolonged ownership.

Early in his career, Buffett frequently bought statistically cheap businesses. Over time, he evolved. Under the influence of Charlie Munger, Buffett increasingly focused on acquiring exceptional businesses capable of compounding internally for decades.

Many of Berkshire’s greatest successes emerged from this evolution: GEICO, Coca-Cola, American Express, and Apple. These investments were not successful because Buffett perfectly timed economic cycles. They succeeded because Berkshire identified businesses with durable competitive advantages and then largely allowed time to work. The holding period became measured in decades rather than quarters.

This is one reason Berkshire generated extraordinary long-term results. Historically, Berkshire’s compounded gains vastly exceeded those of the S&P 500 over multiple decades.

Why Institutions Struggle to Let Winners Run

If the logic is so obvious, why do so few investors implement it? The answer lies in incentives. Institutional investors operate under constraints that individual investors often do not face. Fund managers are evaluated quarterly, annually, relative to benchmarks, and relative to peers. Career risk becomes more important than investment risk.

Suppose a portfolio manager owns a stock that grows from 5% to 25% of assets. The rational decision may be to continue holding. The professional decision may be to trim. The manager must justify concentration to clients, risk committees, regulators, and boards.

Consequently, many institutions systematically harvest their flowers and water their weeds. They sell their best businesses while retaining mediocre positions. Over decades, this practice can destroy enormous amounts of shareholder wealth.

The Difference Between Activity and Results

Modern finance often encourages activity. Investors are constantly told to rebalance, rotate sectors, adjust allocations, manage exposures, and trade around positions. These activities create the appearance of sophistication.

Yet some of history’s greatest investment outcomes emerged from remarkable inactivity. The investment process that creates a 100-bagger frequently looks boring. There are years when nothing happens. There are periods of severe volatility. There are drawdowns. There are headlines predicting disaster. The investor’s primary task is often simply remaining seated.

This is psychologically difficult because inactivity feels unproductive. Humans evolved to solve immediate problems. We are not naturally designed to watch compound interest operate for thirty years.

Nevertheless, patience remains one of the most underappreciated competitive advantages available to investors.

The Behavioural Challenge

The greatest obstacle to investment success is rarely intellectual. It is behavioural. Most investors understand compounding conceptually. Far fewer can endure it emotionally.

• When a stock falls 40%, fear emerges.
• When a stock rises 500%, greed emerges.
• When a stock becomes a large percentage of net worth, anxiety emerges.

Each emotional state encourages action. Yet action is often precisely what destroys long-term returns. This is why investing knowledge alone is insufficient. Temperament matters. Patience matters. Conviction matters. The ability to remain rational during periods of extreme optimism and pessimism matters.

Investors who master these behavioural challenges possess an advantage that cannot be easily replicated by algorithms, databases, or financial models.

What This Means for Quality Investors

As someone who has consistently gravitated toward the “Wonderful Companies at Fair Prices” philosophy championed by Charlie Munger, Terry Smith, François Rochon, and other quality-focused investors, I find Pabrai’s thought experiment particularly illuminating.

The lesson is not that diversification is unnecessary. The lesson is not that investors should place all capital into a single stock. The lesson is that extraordinary investment results frequently originate from a very small number of holdings.

For investors focused on business quality, key attributes become critically important:

When these characteristics coexist, time becomes an ally. The investor no longer requires constant prediction. The business itself performs most of the heavy lifting. The challenge shifts from finding the next opportunity to resisting the temptation to interrupt compounding.

The Final Paradox

History shows that a small number of extraordinary businesses create a disproportionate share of long-term wealth. The challenge for investors is identifying those businesses, purchasing them at sensible valuations, and then possessing the discipline to hold them long enough for compounding to perform its quiet magic.

Virtually all entrepreneurs fail multiple times before building successful companies. Investors are no different.

In the end, the greatest enemy of investment success may not be poor stock selection. It may be our inability to sit still while greatness compounds.