I usually shave at night, when my daughter is already asleep and my wife is halfway there, so there's no problem leaving the door open. even when I shave in the morning I don't bother with closing it. My daughter (3.5yo) is fascinated by the concept of shaving, and it's easier to let her watch and ask questions than keep her out. The cat is only in the yard, and when it comes to bypads ,with the door open I can hear better if someone is approaching. That been said, I try not to let being startled translate into unplanned motion. In too many things I do ( reservist as a marksman and a combat medic, EMT volunteer and first responder, gun owner, IPSC competitor etc) bad things happen if you let loud noises affect your fingers...