Comment by noirscape

There's a difference between software that's "done" (it never needs updates, ever) and software that's done (it only needs maintenance for security and platform churn).

The former is extremely rare; platform churn alone will usually demand updates, even if your code is otherwise airtight. Forces generally beyond your access will demand that your code is able to conform to platform standards. The demand this places can be very variable and depends more on the platform than you. (Windows has low platform churn since it's possible to futz with compat features, Linux is extremely variable on your codebase, MacOS is fairly constant and from what I know about mobile phones, you're basically signing up to forever maintenance duty).

The latter is much more common; sure, sudo still gets updates but most of those won't be new features. Specification wise, sudo is "done". It does what it needs to, it's interface is defined and there aren't going to be any strange surprises when I run sudo between any system made in the past 10 years or so.

The problem is that when you're selling software, demanding compensation for the former is a hard sell since it's things customers won't see or necessarily care about. Demanding compensation for the latter is much more obviously acceptable.