Batteries go south, no doubt. Smoke detectors don't go off much but the battery still drains, we just don't know it until its too late.
So somebody came up with the ideal of changing smoke detector batteries when they change their clocks, twice a year whether they need it or not.
Same thing with batteries in laser sights, they last a long time, much more then a year the way I use them...........BUT........ I change my CT LS batteries when I change my smoke detector batteries, and when I change my clocks...that being twice a year.
I change the batteries in my ear protectors every time I go to a major match, I've had them fail, I can't hear the timer without my electronic ear protectors.
Same thing with car batteries. You don't head into a winter season with poor batteries in your car or truck.
Batteries fail, I know this more then most considering how much time I spent in the Arctic in sub-zero temps.
But I hope I'm smarter then a battery. You can prepare for possible failures with LS batteries just like anything else.
Its not the Laser Sight's fault its ours.
CPT USAR Ret
USAMU Sniper School Oct '78
Distinguished Rifle Badge 1071