My point is, they had an unusual natural talent they were able to tap (maybe not Beckham so much). The talent is primary, the effort is secondary....but no, I don't believe Mozart, Gauss, Da Vinci, Feynman, Einstein, von Neumann, Beckham or anybody in any field just strolled along, picked it up and was world class.
[Although Beckham is a good example for your argument, as consensus suggests he represents a good example of someone who rose to the top of the game predominantly due to hard work. Other footballing examples, such as Gascoigne and Best, support my contention that natural talent can be enough on its own. They certainly weren't obsessives about training!]