[sandoze]

I can’t speak to OS development but industrial coding there’s a lot of experimenting and throw away. You generally don’t write a lot of code for the platform you’re building on (PLCs, automation components). It’s well tested and if it doesn’t hit industry standards (eg. timing, braking) you iterate or start over. At least that was my experience.

When it comes to general software development for customers in the everyday world (phones, computers, web). I often write once for proof, iterate as product requirements becomes clearer/refined, rewrite if necessary (code smell, initial pattern was inefficient for the final outcome).

On a large project, often I’ll touch something I wrote a year ago and realize I’ve evolved the pattern or learned something new in the language/system and I’ll do a little refactor while I’m in there. Even if it’s just code organization for readability.