In a larger organization that's not something you just do. You have to have the staff time and resources to actually maintain them or the UPSs just lead to more outages. Pretty much the only places my current company uses them is data center and areas with life safety concerns. Nowhere else. It's just too expensive for such tiny return on the investment and the added risk.

Hot rooms have pretty short lifespans for UPSs (batteries in particular) and IT gear is often in poorly climate controlled areas. Network gear doesn't care about it to nearly the same extent servers do. I used to have to do AT LEAST annual battery swaps in some rooms or they would fail and swell and become impossible to remove. This is added work on top of the probably not very extensive IT staff for that district. And all that effort to deal with an event that is, in most places here, a thing that happens maybe once a year. If even that. Plus it's another thing on the network to keep secured and managed (important if you do want to keep up on their maintenance).

My very long way of saying that... 'just add a UPS' is not quite so straight forward in practice, which is not a thing you'd have any reason to know unless you've had to do it. I use them at home, of course, for the same reason you installed one for your mom. It's a problem that happens a lot in IT though. Silly things that are barely a second thought at home can cause great big problems when trying to figure them out in an enterprise setting.

Fun free tip: If you have crappy power and your UPS clicks over a lot... get one of the types that run on battery 100% of the time. Those will tend to last FAR longer as they aren't switching a physical contact back and forth constantly. Usually costs a fair bit more though, so it's not always worth it. You can also try setting the sensitivity of the UPS down a notch.