Specifically, Buffett offered to bet that over a ten-year period from January 1, 2008 to December 31, 2017, the S&P 500 index would outperform a portfolio of funds of hedge funds when performance is measured on a basis net of fees, costs and all expenses.
A lot of very smart people set out to do better than average in securities markets. Call them active investors. Their opposites, passive investors, will by definition do about average. In aggregate their positions will more or less approximate those of an index fund. Therefore, the balance of the universe—the active investors—must do about average as well. However, these investors will incur far greater costs. So, on balance, their aggregate results after these costs will be worse than those of the passive investors.
Costs skyrocket when large annual fees, large performance fees, and active trading costs are all added to the active investor’s equation. Funds of hedge funds accentuate this cost problem because their fees are superimposed on the large fees charged by the hedge funds in which the funds of funds are invested.
A number of smart people are involved in running hedge funds. But to a great extent their efforts are self-neutralizing, and their IQ will not overcome the costs they impose on investors. Investors, on average and over time, will do better with a low-cost index fund than with a group of funds of funds.