I suspect the 10X observation is due in large part to the fact that some programmers are more experienced. I'm much more productive than I used to be, because

I suspect the 10X observation is due in large part to the fact that some programmers are more experienced. I'm much more productive than I used to be, because I've been doing it for 10 years. I've already had to think about a lot of problems, which means I already know solutions for a lot of things. It doesn't mean I'm inherently better than I was, just more experienced. I expect that this 10X figure is also applicable to things besides software engineering. I'd guess that auto mechanics with 30 yrs of experience running their own auto shop are 10X more productive at solving problems than new guy at the dealership. (Note: solving problems, not just replacing the part. Knowing what part to replace) The Ph.D. who's been researching for 30 years probably is a lot faster at finding solutions than the guy who just passed his qualifiers.