As it takes me days to draft one scene, I often find myself forgetting THINGS. I try to be mindful of character and place consistency, but THINGS are harder to remember. As I've read (and re-read (and re-read)) my manuscript, I find that THINGS have a tendency to disappear...
The mango and croissant Tess was eating? I definitely did not give her enough time to finish breakfast before she ran into the beach house to change. (Unless she ate it very fast.)
That water bottle she carried as she crossed through the rainforest with Quinn? Well, it ceased to exist when she grabbed a hold of the rope to climb a ruin. (Did she litter? Bad, bad Tess.)
What about the oars they used to beat a path through the island jungle? They really do need them to kayak back to shore, but suddenly Quinn finds his hands conveniently unburdened when he pulls out his camera.
Now the spear. (Oh the spear.) When I chose a fifteenth-century Spanish soldier as one of my heroes, I didn't consider that he'd be toting a spear half the time. He just rescued a small boy, and the spear happily vanished when he needed to lift the child off the ground.
Do you have trouble keeping tabs on all your literary props?