@chris__martin @dalias > "why does software require maintenance"

Improperly defined interfaces between systems & libraries and software, most of the time.

Then there's the odd once in a while (often with decades-long spacing) that one needs to change something to support a new system entirely.

> what matters is its relationship with the surrounding context, and that context is in perpetual change.

That's mostly true for software with unlimited scope. It is perfectly possible to have software that is /complete/ and needs no more maintenance than the second example I gave above.