Regression to mean of a random walk.
There's lots of "brilliant" worship in the mainstream and especially among techies. We strive to be geniuses too, never mind one falls and another replaces him. And luck? That's the opposite of what we want to believe.
But to be fair, outlier success in many fields is rarely possible without some initial high level of skill and knowledge in the first place.
> More likely it is “regression to the mean”, or in simple terms, a return to business as usual.