Interesting research challenging the '10,000 hours' claim that hard work is sufficient to be great at something.
digest.bps.org.uk/2014/06/30/exploding-the-10000-hours-myth-its-no-guarantee-for-greatness/
The hours practised by grandmasters in a chess study went from 832 to over 24,000 and there were players at intermediate level who had practised for longer than the average grandmaster.
I think people already knew this really, but the whole 'growth mindset' fad of recent years has been promoting the idea that anyone can be great at anything. Obviously if you work hard at something, you can get better at it, but there are also other factors at play.