Think of Murphy everytime you go out into world.
Because its going to be that one time (out of 1,000) that you decided to leave your firearm at home because you forgot to clean it last night, or you were late to work, or you were in your car driving off and then the event you have been preparing for happens....
When did Noah build the Ark? Before the rain, before the rain.
First tactical advantage: From the boy scout motto: Be Prepared.
First Law of a gunfight: Have a gun.