http://en.wikipedia.org/wiki/Outliers_(book)
Gladwell repeatedly mentions the "10,000-Hour Rule", claiming that the key to success in any field is, to a large extent, a matter of practicing a specific task for a total of around 10,000 hours.
While there are lots of factors outside of a person's control which will help/hinder their chances of success, the most important factor is the effort they put into it.
Essentially, being the most naturally talented basketball player or software developer is meaningless unless you put the time in to develop your skill to achieve your potential; and anyone who puts that kind of effort into developing their natural talents will also end up achieving significant success.
Or to put it another way ...
When I was in high-school one of my classmates played football with me. Even though he wasn't in (particularly) good shape and he smoked he had the ability to run 40 meters in under 4 seconds. His natural athleticism actually attracted the attention of several scouts from large US colleges which is unheard of in Canada. This all resulted in him being offered a couple of scholarships and all he had to do was write the SATs and graduate at the end of the year. While it is difficult to understand the logic behind it, he skipped several classes a day from the time the football season ended in grade 12 and eventually was expelled from school; and never graduated.
All the natural talent in the world doesn't matter if you screw up your opportunities; and (realistically) far more people screw up the opportunities they had then failed after putting in the effort needed to achieve their potential.
