[stephenr]

> when I'm on the desk, I always have the charger in.

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.

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.

[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.