index funds.Lack of Reactive Ability

Sometimes obvious mispricing can occur in the market. If there’s one company in the internet sector that has a unique benefit and all other internet company stock prices move up in sympathy, they may become overvalued as a group. The opposite can also happen: One company may have disastrous results that are unique to that company, but it may take down the stock prices of all companies in its sector. That sector may be a compelling value, but in a broad market value weighted index, exposure to that sector will actually be reduced instead of increased. Active management can take advantage of this misguided behavior in the market. An investor can watch out for good companies that become undervalued based on factors other than fundamentals, and sell companies that become overvalued for the same reason.