As Claude says in his article, you shouldn’t pick up your home defense gun if you don’t have a light on or near it. There are too many instances of home owners putting a bullet into a loved one. Totally preventable with a $5 flashlight and a minimal amount of training. In training courses, the emphasis of rule 4 (be aware of your target and what is around it) is placed on the backstop or people moving around the thing you intend to shoot. When I teach it, I put an emphasis on the target itself. Please make sure you identify what you’re shooting at. Don’t be afraid to use your words and verbalize. You have to practice speaking with a gun in your hand. It’s not natural, so do it when you dry fire.