casino owners compete with each other. Lots of casinos fail, but you don't get interviews with failed casino owners. (edit: I just realized that there is one, v

casino owners compete with each other. Lots of casinos fail, but you don't get interviews with failed casino owners. (edit: I just realized that there is one, very notable exception to this) If the only difference between a successful casino strategy and an unsuccessful one is failure to control for some variable, then the variance in that variable will yield some very successful casinos, and some unsuccessful casinos, regardless of the actual expected value of the casino business.