To avoid, at all cost, any situation that might remotely result in a failure on your, and your liabilities, part.
Stan: "Hey man, let's go to the mall, I want to get something to eat."
Sami: "Nah man, you're only hungry because you have post-high munchies. We should wait at my house before we go out anywhere. Plus, I have some Doritos at home you can munch on."
Stan: "Sweet, failsafe."
Sami: "Hey Charlie, can me and my girlfriend skip school at your house?"
Charlie: "Sure, but you'll have to leave before 12, my mother might come home early for lunch. Gotta be failsafe man."