“Diversification is a way to protect financial consultants and stock brokers from ever looking really bad, but it also stops them from looking really good as well. What happens with broad diversification—holding a portfolio of, say, fifty or more different stocks—is that the winners will be canceled out by the losers, just as the losers will be canceled out by the winners. Diversification creates a situation that basically mimics the market or an index fund. An adviser who counsels diversification never looks very good or very bad, just average.”