When a customer is looking for a certain store item and they ask an employee to check in the back inventory for it.
Guy : Yo you got a t-bone steak?
Employee: Sir, this is a baby food store.
Guy: Uhhhhh check in the back, the FAR back for dat shit.
Employee: Damn wow we actually have one left
When you are bored or you've been away from Internet access or just whenever you log in to Facebook over and over even though pretty much nothing changes, but you just do it to a) have something to do b) make sure no one's magically done something cool. Called such because it's like when you're hungry or (more likely) bored and so you keep checking the fridge in the hopes that something new and exciting will appear, even though you know it's just week-old leftovers.
Dude 1: Hey, have you noticed Lou's been on Facebook a lot today?
Dude 2: Yeah, he was camping all last week...must have the Facebook Fridge-Check Syndrome.
A "check-in-the-box" and is an action or mandate that a group or authority takes when it doesn't want to be liable for something, so they put on an act that everyone secretly knows is functionally meaningless but has enough good intention so that criticism is often viciously attacked. In the end, if a worst-case scenario presents itself, the group or authority in question can claim they took all the possible precautions they had at their disposal and are not liable for damages while exclaiming how sorry they are things didn't happen as they would have liked. This usually leads to calls for more feel-good protocols and additional checks-in-the-box actions, and if the group or authorities' performance is good enough can even lead to the group or authority being lauded for their benevolence, all the while the people forgetting it was the original check-in-the-box that might have caused the crisis.
Person A: Do you think installing a sign warning people that there is no lifeguard on duty will help prevent drowning?
Person B: (Being honest) Of course not, but it's a check-in-the-box, so we won't be responsible if anything else does happen.
Person A: You're so cynical.
The term used to describe the monotonous, rigorous, stab-your-eye-with-a-pencil military process of completing useless routine activities to be rewarded with a check mark on a piece of paper.
"Yeah! In-clearance took 2 days and I filled out the same form 8 times, but at least I got my check in the box for another year!"