The stock market may be “crushing” Berkshire Hathaway, but that doesn’t mean Warren Buffett has lost his touch, according to a recent MarketWatch article by Larry Swedroe, chief research officer at the Buckingham Family of Financial Services.

The problem isn’t that Buffett is off his game, writes Swedroe, but rather that “the value premium in U.S. stocks has been negative for more than a decade. Since Buffett’s investment strategy has always been value-oriented, this might explain the gap between Berkshire and the S&P.”

Swedroe explains that while the long value drought isn’t necessarily unusual, “Buffett knows it shouldn’t be unexpected. He knows that all risky assets experience long periods of underperformance. It that weren’t the case, there would be no risk for long-term investors (and there should not be any other kind).” He cites two cognitive biases as contributing factors:

Recency: “recent observations have the largest impact on an individual’s memory and, consequently, on perception;”

Relativism: “investor satisfaction or unhappiness and, by extension, the discipline required to stick with a strategy is often determined by the performance of the portfolio relative to some index.”

These “twin problems,” Swedroe explains, are compounded by the fact that most investors think “three years is a long time, five years a very long time, and 10 years an eternity.” But he notes that financial economists believe otherwise and, when it comes to risky assets, “performance over 10 years is likely nothing more than noise.” For this reason, Swedroe asserts, Buffett believes that investor temperament is “far more important than intelligence” because it provides the discipline necessary to stick to a strategy and ignore periods of underperformance.