Getting charged

jeep liberty 02.parked it,sitting for a while.couple of weeks.walked by it heard rear door lock activating so i unhooked battery.tried starting it but is dead.so i tried charging it but it was discharging kicking of the charger.tried jumping it but it was discharging.so i unhooked battery altogether tried jumping terminals but it still trying to discharge ,why?

see above/below-no need for multiple posts.