When I can't see to shoot. I usually come down. then, if I am hunting in the woods, off of a field, I will move out to the field and wait till it is to dark there. The woods is usually darker a lot quicker.

if i have a hard time finding the truck without a flashlight... i waited long enough

You do know that deer can see pretty goodin the dark, don't you?

During bow season, like others have said, when I can't see well enough for a clean and safe shot.
During rifle season, when legalshooting hours are over. I stay right 'til the last minute, then begin my 1/2 hr. walk back to the truck.

Yesterday I was on top of a large hill. I waited until I could barely see, but there was still some light. After I got my stand packed away and on my back, there was still a hint of light to walk, but not enough to make me remember that old barbed wire fence that I saw on the way up, that I tripped over, causing my stand to flip over my back and hit me on top of the head. I'm lucky I didn't kill myself.