Many garages and tire shops store their customers' summer or winter tires. Twice a year hundreds of sets come in within a few weeks, and each one has to go somewhere in the racks.
A paper tag on the tires and a handwritten list in the office work until the list is incomplete. When the customer arrives for the change, someone walks the racks reading tags while the car waits on the lift.
A barcode on every rack slot and every tire set label turns storing into two scans per set, and finding a set into a lookup.