reaching master level performances in chess is to engage in at least 10 years or 10,000 hours of deliberate practice. Moreover, Ericsson claims that the primary source of individual differences in chess skill is deliberate practice time.
Anybody at around average intelligence can be good at chess, but when you're talking about the top 100 in the world all those people work hard so the only thing that can differentiate them is genetics. Absolutely.
