[awb]

The Sharpe ratio (https://www.investopedia.com/terms/s/sharperatio.asp) attempts to quantify risk-adjusted returns by accounting for the standard deviation of the portfolio.

So even if an average angel investor produces higher average returns than SPY, they might still have a lower Sharpe ratio, meaning the angel is taking on much more risk for only slightly higher returns.

For most investors it's hard to beat a broad market ETF for risk-adjusted returns.