I think, that regression to the mean might be one of the worst explained phenomena out there.

It is ridiculously simple logical process, but noone istalking about the source of it, so people always assume that it will infinitely pull people down.

So, what is it? If you take 2 people with IQ of 150, and they have kids, their IQ will be 145.

Why? Because every single factor in this world is affected by luck. The world is way too complex to be measured correctly. So, everyone has properties separated to "true value" and lifetime luck. And when you take 2 above average people, there is a huge chance that their lifetime luck was also above average.

So, the parents might have a true IQ of 150+0, while the other parent has 140 with 10 points of lifetime luck, that managed to make results higher. But, that luck will not affect the next generation, meaning that only the real part of their IQ will be averaged.

But this new average is real, and there will not be a 2nd round of decrease.