[aj0strow]

I don't have data, only personal experience. See: https://en.wikipedia.org/wiki/Concerted_cultivation

Malcolm Gladwell writes about this too, in Outliers [1] (chapters 3 and 4). His aim was to dispel the myth that success derives from intelligence.

[1]: https://www.amazon.ca/Outliers-Story-Success-Malcolm-Gladwel...