If markets are fully efficient, investment managers who focus on discovering mispriced stocks would be in a bind. Recent research by Dimensional Fund Advisors has found that most fund managers underperform their benchmarks.
The stock market aggregates vast quantities of information into stock prices, including the daily trades of millions of buyers and sellers. When mutual fund managers look for mispriced securities, they are pitting their insight against all market participants.
How many mutual funds consistently outperform their benchmarks? Look at Dimensional Fund Advisors research to get an idea of manger performance and the power of market prices.
Mutual fund investment values will fluctuate, and shares, when redeemed, may be worth more or less than original cost. Diversification neither assures a profit nor guarantees against a loss in a declining market. There is no guarantee investment strategies will be successful. Past performance is no guarantee of future results.