Your example was quite good actually. Even in sw the people that build the system is not necessarily the people that monitor, maintain and use it, even for systems used only inside a company. I used to work in a telco and we had 3 separate departments, plus a 4th one for testing. And yet all of them seem to be subject to section 174, builders, maintainers, testers.
A country wide power grid or telecommunications network are other examples that come to my mind. They are never complete, they get more features every day (new cables?), they are monitored 24/7. The owner companies also use them.
> And yet all of them seem to be subject to section 174, builders, maintainers, testers.
Do they?
Upthread one can read: > Activities that are not treated as software development vis-à-vis software developed by a taxpayer for use in its trade or business are as follows: […] • maintenance activities after the taxpayer places the computer software into service
You are right. I also read other comments pointing at that. Nevertheless it's often debatable what's maintenance and what's a new feature. Hopefully nobody is looking at it in too much detail.
Example: a one line change to ignore non Unicode codepoints in PDF files loaded in a web app (I did it yesterday.) Is that a new feature? Is that a bug fix? And if it's a bug fix, is that part of a feature that we should have developed before putting the sw into service? Is that maintenance? And what if that particular code point that triggered the issue did not even exist when we released the sw years ago (the code around it is from 2021)?
I believe that nobody has the time to dig the (tens of?) thousands of issues that a company opens and completes every year but there are a lot of gray areas to exploit if somebody has any reason to be pedantic.
> Nevertheless it's often debatable what's maintenance and what's a new feature.
The same is true for many capital assets. There are people who have time to look into these things because that’s their job.