I plugged my phone in to charge at night (was not dead, probably 30%). When I wake up 8 hours later, I look at my phone to see that it only charged to 93%. I unplugged it and then plugged it back in while I got ready. About 30 minutes later, I look at the phone and it's fully charged. Is there a reason as to why my phone did not fully charge? This has happened multiple times.
I was charging it with the wall adapter, if that matters.