It doesn't limit anything. Let's say you put 100k in the market today. With probability p you will have 8% return at some unknown point in time in the future (y

It doesn't limit anything. Let's say you put 100k in the market today. With probability p you will have 8% return at some unknown point in time in the future (your argument may be false even from a simple temporal point of view, take a day in which the market plummeted, and take the closing price of that day, not the end of the year value, and 20 years prior I doubt you would have made a profit, but I can't make any statistics as of now). That means your 8% is unknown. So you haven't really mitigated any loss. The distribution of returns is unknown, at any time period, dayly, yearly, whatever, so you can't know your p, so any wishful calculation is nothing. Now, let's assume what I said up to now is wrong. I don't pretend to know the absolute truth anyway. Reflect on this: even if something has made a profit buying and holding for 20 years consistently for a millennia, it means nothing for my future. What guarantees me that I will make my profit in my 20 years? I can't travel back in time. Before discovering black swans, everyone thought swans could only be white. Also, 150 years of data on a phenomenon that changes almost daily is nothing.