This natural proclivity is essential in order to do the hard work, and to have the motivation to excel and take whatever skill to the next level.
That really sums it up beautifully in one paragraph, like you say, you have to have the interest and the drive to even embark on the journey in the first place, and therein lies the whole point. Perhaps, natural talent, is simply the ability to be able to do something over and over again without getting bored. If you can do that, you have a chance.
Plus of course, your brain has to be wired a certain way; however maybe they are just two sides of the same coin. The part of Mozart's motorcortex that controlled his fingers, was wired in such a way that his fingers, moved just so (plus he had synthesise), which meant that he found it fun to practice and practice, and practice.
Luck is a funny one; and I am a great believer of making your own luck; I have explored it in the past here, and may again do it in the future. However as far as I can see it, luck is simply an illusion that others perceive, to the person it's happening to, it rarely seems lucky; rarely but never, I guess :-)
Thanks for your comments, I really enjoyed mulling them over and answering :-D
Cg
You're right - when one is lucky one rarely realizes it and also that luck is a tricky subject that can be refuted. One other point worth mentioning is that I don't believe we're all equal in "talent", motivation or our potential . This is a controversial thing to say and I've change my mind about it at different times in my life, but at this point I do believe we all have a talent for something but those who have the unique ingredients for extraordinary talent are, well extraordinary! Anyway, thanks for the thought provoking post as always and in depth response.