I would have to say that it is a tie between my movement in stand and scent control. I spray down and keep my clothes in a scent free bag so they don't pick up any odors. I always check the wind before I climb into a stand.By movement I mean I stay completely still or limit it to the minimum. I wonder how many times deer have seen me before I have seen them and got out quietly without me knowing. I practice on squirrels and turkeys. If you can move without a red squirrel or especially a turkey seeing you then a deer never will when it is crunch time.