Always?
Or are you showing a selection bias?
I call it "hitting your head against a brick wall". The tenacity to keep fighting until you win. Doesn't always work (can end up wasting time) but it is surprisingly effective against seemingly intratible problems. "Grit" is the marketing word. Workarounds is another form.
I'm interested in how it can be taught. I force myself because I admire a certain level of "OCD" behaviours and try to emulate those I admire.
I think it's best learnt through encouragement and support. If I have one takeaway for the last 5+ years of teaching, it's that most barriers to learning are emotional, not intellectual.
Is this what people think of when they think of an old codebase? Must be nice :')
15 years of active feature development on the other hand will likely be a major slog for any developer, regardless of experience. There's a lot that can happen in 15 years even if there were only 1-3 developers if they everyone takes the easy path since they know where all the gotchas are. It's only when new devs are added that the curtain comes down and the lazy abstractions (or lack thereof) are exposed.