My Microsoft Band 2 seems to have finally died on me. On the bright side, it lasted over a year.
And it didn't tear. That's by far the leading cause of death for these things, but against all odds, mine managed to stay in one piece.
I don't know exactly why it's dead, but I strongly suspect it happened after it smacked into a pole on the bus. (Obviously not intentionally.) I noticed it wasn't turning on a little while later, and wondered if I'd just forgotten to charge it overnight. I got home and connected the charger - it started up again, and asked me to set the time again as the battery "ran out".
But no, it doesn't hold a charge any more. It dies when I take it off the charger, and it doesn't seem to work properly even when left on it. I guess something's loose on the inside?