Comment by veeenu

This is widely known among practitioners, but there is a caveat -- a 1/N portfolio bears a much higher risk than, say, a cap-weighted portfolio or a risk-parity asset allocation. A 1/N portfolio receives an equal contribution in terms of volatility from each asset, meaning that very risky assets significantly increase the portfolio's volatility, while not necessarily contributing proportionally better returns, due to the nonlinearity and asymmetry of volatility's effects on prices. This way, 1/N ends up performing very poorly on a risk-adjusted basis while undoubtedly at the same time outperforming any other kind of allocation on the basis of return alone. This is rather unacceptable in a real world portfolio where the tail risks and emotions can lead an investor to ruin.