[txutxu]

> Unless the machine specifically handles this scenario, this can artificially wear the battery. Newer MacBooks handle this better with "intelligent" charging (I couldn't say for sure whether a 2012 MBA would have had this feature), but I don't know about other brands.

Yes... this is why I did use to take it out in old laptops while not moving from the desk.

With my thinkpad, I used to do:

    sudo tlp setcharge 60 95 BAT0

This means: "start charging when level is 60% and stop charging when it reaches 90%"

> But the real answer here is that batteries are essentially consumable parts. They won't last forever, and once it drops below holding ~80% of the original charge, it's worthwhile replacing it.

Indeed, probably for the extensive use I do, it's normal to do not pass the 3 or 4 years of good conditions.