I am not sure the ones the do at the auto store, but wearing a battery down is not good. How bad, canbe debated and depends on the tests. Even thiough destructive sometimes you have to do them for legal reasons. We got batteries 25 years old or more.

But I always charge my battery the night before Is start in the spring, in order to not stress it. Maybe I should do it at end of year, but I don't.

I work on 48-230vdc. In my arrogant opinion, most people should stay away from electrical.

If use your meter to test the voltage into the voltage reg, and than the voltage into the battery, load testing batteries is a waste of time. I just got better things to do, than pull battery and drive around with it.

 

Same thing just happened to my 1994 Road King. Its the battery.