Mainly because of fees and trading-related costs, the vast majority of actively managed funds are unable to beat their benchmark index over long time periods. Using past performance to pick actively managed funds does not improve your chances of beating the index going forward.
Long Time Horizons
And the Investment Edge They Provide - Explained in a Dozen Charts
Short-term equity market returns are volatile and unpredictable. Long-term returns are much less volatile and fairly predictable with the use of sound valuation analysis. Disciplined investors with long time horizons have a distinct investment edge over other equity market participants, particularly those with short time horizons.