[gloryless]

This is an unhelpful oversimplification. There are lots of tasks that are maintenance, and the more code your team has written the more these tasks build up. I don't know what motivates someone to pretend it is the same as writing new features, but it deals with distinctly different risks.

[throwaway_au_1]

I think it's sensible to be critical of the language used in our craft, especially when borrowed from the more physical world, because with it comes the baggage. For example, I have a pet peeve with the phrase "use the right tool for the job" used in the context of languages/stacks, because languages and stacks are more akin to building materials than tools (IMO). Selecting a building material and selecting a tool involve different considerations, and thought-terminating cliches like the above can give a false sense of clarity. So IMO, to look at software maintenance as the author has done, I think is fair and reasonable, even if just to render obvious that software maintenance is a special variety of maintenance that differs from most usages of 'maintenance'.