The risk with this sort of analysis is that the results depend on the time period you pick. If cycles truly always brought your returns down to zero, how would you explain that over the very long term (over a century), the market has a positive average annual return of more than 10% (about 7% adjusting for inflation)?

I'm not saying there aren't cycles, just that I don't think they revert to zero, but rather to that very long term average return.

What am I missing?