A bag tag is a promise: this piece belongs to that passenger, on that flight, going to that airport. Baggage reconciliation is the practice of checking the promise at every point where the bag changes hands.
BRS follows the bag from acceptance to the hold. Each scan updates its state — checked-in, reconciled, loaded, offloaded, returned — and ties it to a passenger, a flight and a container. The states are not paperwork. They are the answers to questions somebody is about to ask under time pressure.
The sharpest of those questions is the offload. A passenger checks a bag and does not board. Regulation and good sense say the bag does not travel either. Without reconciliation, answering that means opening the hold and searching, with the clock running and a departure slot at risk. With it, the bag's last known container and position are already recorded, and the request is answered in seconds.
The same record does quieter work all day. Grouping bags by container, bay and sequence makes the make-up area legible during a peak when several flights share one hall. Live counters — checked-in, reconciled, loaded, to-offload, offloaded — let a supervisor see whether a flight is actually ready rather than assuming it is.
Because the workflow runs identically on a console in the office and on a handheld beside the aircraft, the ramp and the office are not reconciling two versions of the day afterwards. They were never looking at different data.
When something does go wrong, the value is the history: where each bag was last seen, when, and who scanned it. That is the difference between an incident you can explain and one you can only apologise for.