The typical claim is stock market returns are entirely random, not based on skill, so any returns that beat the perfectly efficient market are purely due to cha

The typical claim is stock market returns are entirely random, not based on skill, so any returns that beat the perfectly efficient market are purely due to chance. Beating the market (no matter the margin) is purported to be a 50-50 chance, and doing so 40 times in a row would happen by chance less than 1 in a trillion times. (That is, if you accept the premise that stock market investing has no skill component.)