Since investors form irrational expectations of the future, they make systematic investing errors. This can be seen in the track record of mutual funds. Fund managers, who are supposed to be experts paid to invest other people's money wisely, consistently become fully invested near stock market tops and are relatively underinvested near market bottoms. Of course, if they were rational investors, fund managers would seek to maximize their returns by selling near tops and buying near bottoms rather than vice versa, but the evidence shows the opposite to be the case: