Why does my Gear S2 battery drain so quickly?

[Android Central Question]

My Gear S2 is on power save mode, was at 100% when I went to bed at 9:45pm and when I woke up at 7:20am, it was at 4%. Has been on charger for 1 hour 25 minutes and is not fully charged yet.

 

[B. Diddy]

I moved this to the Gear S2 forum for more specific traffic.

 

[S2user10]

My 2nd day was like this. I hard reset, then deleted the app. I started tweeking. I shut off mobile network. I shut off wifi. I checked and deleted apps I don't use. CNN etc. I unchecked auto updates. I unchecked show only while wearing. Put phone on airplane mode at night while charging. Started out with 100%battery I now have 16 hrs left at 4pm. Yesterday it didn't last till 2pm.