Understanding your target audience (domain). A mediocre “Programmer” who can understand exactly what the customer/user wants and how it impacts them will outproduce a wiz programmer who concentrates on making the algorithms “perfect”.
If what the audience wants is a way to made 3=2 then writing an algorithm that shows that 3<>2 in under 2 seconds is going to be worse than an algorithm that makes 3=2 even if it takes 20 years.
Many times programmers forget the reason they program. I always look at it this way.
1. We write programs for end users. The end game is to make a program that the end user will use. It doesn’t matter to them usually if a function call takes .0003 sec or .0002 sec. Knowing what the end user wants and being able to put it out is 10X more important (and profitable) than knowing how to code quickly.
2. We write Code for other programmers (and ourselves). The code we write has to be able to be available to other programmers or ourselves months or years later. That means that no matter how efficient a control table with a 256byte ascii translation key is, knowing what the heck it is doing by looking at the code 6 months from now is likely to be a problem, so unless it’s necessary to get #1 above done (maybe it’s happening in a loop and you need the performance) it’s an inefficient choice.