Screwup Proofing is why I use a timer.
Infallible reliability is why I chose the Intermatic mechanical windup timer.
Saving a few dollars which destroys a few thousand fails the wisdom test utterly.
For example when I did battery cycle testing, I chose a 12-volt powered OMRON timer that over-rode the voltage limit switches. Destroying a pallet of L16s was not an option.
The fact that the wind up timers work in commercial restrooms is a testament of their reliability and ruggedness.
Are they accurate? Down to the minute? Hell no. Did I need resolution down to the minute? Hell no.
I just needed an absolutely reliable cutoff without being forced to learn c++ programming language.