This. It seems like it boils down to IQ, trait conscientiousness and the randomness inherently present in a complex, dynamical system. I think people understi

This. It seems like it boils down to IQ, trait conscientiousness and the randomness inherently present in a complex, dynamical system. I think people understimate or ignore the randomness aspect because you can't measure the way in which it contributes. But it's such an important factor. Randomness can generate circumstances that push and pull people at all ends of the distribution in all different directions. That not a trivial thing. The detractors seem to want to focus on "well it's not a perfect predictor". Right. And you're not going to get one in a complex, dynamical system such as this. But in case you were looking for some model that paints a roughly accurate picture in broad strokes, here's one we prepared earlier.