I think there's a human-nature problem to teaching ROI like you suggest. People are always going to think that they're going to be the one to break through--to

I think there's a human-nature problem to teaching ROI like you suggest. People are always going to think that they're going to be the one to break through--to rise above the mean ROI. That's why you get so many people trying to become actors or musicians or athletes or even startup founders. The high-end returns are so distracting that people forget about the mean ROI.