A very good read here from game programming legend John Carmack.
In reality in computer science, just about the only thing that’s really science is when you’re talking about algorithms. And optimization is an engineering. But those don’t actually occupy that much of the total time spent programming. You know, we have a few programmers that spend a lot of time on optimizing and some of the selecting of algorithms on there, but 90% of the programmers are doing programming work to make things happen. And when I start to look at what’s really happening in all of these, there really is no science and engineering and objectivity to most of these tasks. You know, one of the programmers actually says that he does a lot of monkey programming—you know beating on things and making stuff happen. And I, you know we like to think that we can be smart engineers about this, that there are objective ways to make good software, but as I’ve been looking at this more and more, it’s been striking to me how much that really isn’t the case.
The whole post is worth a read.