I've worked on / designed many UPS systems over the years, and have not really come across many blatant over-charging scenarios.
The main issues I come across - 1/ battery balancing ie NOT properly balanced, thus one or more go lower and screw up the levels for all.
I find this to be the #1 killer, by far. Yeah, some chargers are set a bit high (on trickle), but good batteries should have a reasonable margin.
2/ Sedimentation. Unless you select a specific type of lead-acid that doesn't require some vibration to keep the plates clean, it shortens their life.
We buy specific made types from
www.snaptec.com.au/industrial-batteries.html and are getting 10yrs (or longer), sitting in camera towers, out in the
hot sun. Funnily enough, UPSs that have noticeable vibration (from the DC-AC converter) actually help battery life.
The problem has become so common lately, I have started making up a balancer (using the LTC3305)
Now, this may not be your case, but stuff to keep in mind. Either way, if you use properly rated batteries, you can eliminate possibilities.