Well, not really; given enough fools who think they can successfully beat the marker, even in the absence of any actual ability to do so, some number of them wi

Well, not really; given enough fools who think they can successfully beat the marker, even in the absence of any actual ability to do so, some number of them will manage to for a few years by making riskier bets than would be optimal. So if someone tries to get you to invest based on their past performance, you have to consider how many people there are out there trying to beat the market to determine whether this person has any actual skill or just got lucky (and will proceed to lose a bunch of your money by making said overly risky bets).