I ALWAYS close and lock the door. No matter if Im home alone or not. And it doesn't matter if Im home alone, not excepting anyone home for days, and I know no one will stop by. I always shut the door and lock it. Even in the middle of the night. I may hurry down the hall without turning on anylights (even the one in the bathroom), but darn it, I lock that door! I like my privacy and keeping that door shut and locked secures it for me. Even if there is no one to secure it from. I dont think I could go if I didn't.