Research by Bessenbinder shows that a tiny fraction of "superstar" companies drive all market gains. Since identifying these winners in advance is nearly impossible, indexing ensures you own them by default, capturing the market's overall growth without the risk of picking the wrong stocks.

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Most of an index's returns come from a tiny fraction of its component stocks (e.g., 7% of the Russell 3000). The goal of indexing isn't just diversification; it's a strategy to ensure you own the unpredictable "tail-event" winners, like the next Amazon, that are nearly impossible to identify in advance.

While Berkshire Hathaway is built for durability, the S&P 500 index possesses a unique long-term advantage: its self-cleansing mechanism. As dominant companies inevitably falter over centuries (e.g., NVIDIA), the index automatically replaces them with the next generation of winners. This constant rejuvenation could make the index a more resilient investment over an extremely long timeframe.

The asymmetrical nature of stock returns, driven by power laws, means a handful of massive winners can more than compensate for numerous losers, even if half your investments fail. This is due to convex compounding, where upside is unlimited but downside is capped at 100%.

Owning a broad, cap-weighted index fund eliminates the need to predict market winners. As dominant companies like Sears fade, they are replaced by innovators like Amazon. The index automatically adjusts, selling off losers and increasing holdings in rising stars, ensuring you always own the future.

The underperformance of active managers in the last decade wasn't just due to the rise of indexing. The historic run of a few mega-cap tech stocks created a market-cap-weighted index that was statistically almost impossible to beat without owning those specific names, leading to lower active share and alpha dispersion.

The current market is not a simple large-cap story. Since 2015, the S&P 100 has massively outperformed the S&P 500. Within that, the Magnificent 7 have doubled the performance of the other 93 stocks, indicating extreme market concentration rather than a broad-based rally in large companies.

Contrary to the belief that only a few mega-cap stocks drive market returns, a significant portion of S&P 500 companies—167 in the year of recording—outperform the index. This suggests that beating the market through stock picking is more attainable than commonly portrayed.

Even for the world's greatest investor, success is a game of outliers. Buffett made the vast majority of his returns on just 10 of 500 stocks. If you remove the top five deals from Berkshire's history, its returns fall to merely average, highlighting the power law effect in investing.

The stock market is like a casino rigged for savvy players. Instead of trying to beat them at individual games (stock picking), the average investor should "bet on the game itself" by consistently investing in broad market index funds. This long-term strategy of owning the whole "casino" effectively guarantees a win.

Durable Capital founder Henry Ellenbogen's research shows that over any 10-year period, only about 40 of 4,000 public companies compound at 20%+ annually. Critically, 80% of these “valedictorians” begin their compounding journey as small-cap stocks, highlighting this market segment's importance for long-term growth investors.