The following quotations are from Daniel Levitin, a neurologist and the author of "This is your brain on music":
"The emerging picture… is that 10,000 hours of practice is required to achieve the level of mastery associated with being a world-class expert — in anything. In study after study, of composers, basketball players, fiction writers, ice skaters, concert pianists, chess players, master criminals, and what have you, this number comes up again and again."
"Ten Thousand hours is equivalent to roughly three hours a day, or 20 hours a week, of practice over 10 years"
"No one has yet found a case in which true world-class expertise was accomplished in less time. It seems that it takes the brain this long to assimilate all that it need to know to achieve true mastery"
I think 10,000 hours is just an approximation, yet it seems to reflect reality.
Three hours a day, seven days a week, is about 10,000 hours — in 10 years.
Malcolm Gladwell, the author of "The outlier" also mentions the "10,000-Hour Rule", and claims that the key to success in any field is practicing a specific task for 10,000 hours:
"To become a chess grandmaster also seems to take about ten years. And what's ten years? Well, it is roughly how long it takes to put in ten thousand hours of hard practice. Ten thousand hours is the magic number of greatness"
If one wants to be the best at anything, beside the special talent one is gifted, it's also about putting in the hours of practice daily for years!
Talent along will not make one outstanding if one has not put in the time to practice and perfect it.
It is practice that makes perfect!