Quote from coolweb:
Espically in sports...
Most superstars were already superstars when they were young, like 13 years old.
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Find someone who ventures into pro basketball in their 20s, and try to make it to NBA.
There will be around 0.
Either you make it early, Or you'll never make it at all.
Professional sports is different because humans peak physically in their 20s, hence you have to start young because it takes many years of practice and hard work to reach a level of performance that places you in the elite.
With non-athletic professions, such as trading, you can start anytime before 40 and still have time to gain experience.