There are 10X programmers.
I'll give an example. If you take an average programmer and "the best of the best" and ask them to build a relatively complex iOS app, of which neither has previous iOS experience, the best programmers WILL finish the task up to 10x faster than the average.
This is because the average programmer gets stuck on bugs, solving problems, complexity, and is slower at learning new things. The better programmer has a combination of skills that allows him/her to do the correct research and solve the problem at a much faster space. The rate of which grows as the complexity of the task increases. Thus reaching 10X.