I’ve heard repeatedly that there is an order of magnitude difference between the most and least productive programmers. I have no doubt that’s the case, but recently I’ve experienced that difference first hand, and I’ve also come to appreciate the effect of experience on that difference.
We hired a new QA engineer a couple of months ago, and I’ve been working with her closely the past few weeks. She’s very smart and seems to have high technical aptitude, but she doesn’t have much experience with the type of tasks we’ve been working on–dealing with various DBMSes. I’ve worked repeatedly with three of the four DBMSes and know quite a bit about the subtle differences between them. Furthermore, I’ve worked with DBMSes enough to know how to figure out how to do different tasks in each one. This experienced also helped me to get up and running with the one (DB2) that I’m not experienced with.
In this situation, I was an order of magnitude more productive due to my experience.