If you are using rechargeable batteries, lettinug them run completely down is a good idea. Rechargeables can develop "memory," which means a static charge which builds up every time the batteries are charged when they haven't been drained. Eventually, this will rob the batteries of charging capacity. I highly recommend running down rechargeables as often as possible.
(This is not just anecdotal, either. The literature for some of the security devices we sold--such as battery powered covert cameras--advised this, as well. It is, apparently, very common with NiCd batteries.)
I've been aware of the issue with NiCads since the '70s, but thought the problem didn't affect the lithium rechargables. I'm going to stick to the old alkaline anyway. By the time the batteries and charger paid out, the mouse will likely be dead, anyway. The last one lasted since 2007
Remember the old story about "If cars were computers?" Your car would get 500 miles per gallon, zero to sixty in under four seconds, with a top speed approaching supersonic. If it were made by MicroSoft, it would also get hijacked every twenty miles, require a keyboard command to turn a corner, and crash three times a month. Now we discover that if we want to shut off the engine, we've got to pop the hood and pull the ignition wire.
Plus it would ocassionally stop running and you would pull over the side of the road and restart. People wouldn't think anything of this.
I used to have a Ford Taurus that did just that. Worst car I ever had.
I have your mousie's twin bro, Rog, and am perfectly happy with it. It's true that the battery replacement can be irksome, especially if it occurs with some frequency, but -- what the hell! -- I can always use the pad on my laptop if the mouse breaks down.
I'm sure I can live with it, but geez Louise! Couldn't a top flight electrical engineer have tossed in a switch?
Okay, they finally died. Three months ain't bad, I guess, since MicroSoft still doesn't know about switches.
Boy, when it died, it just stopped in it's tracks.