Sorry to hear about the lost luggage if that's happened to you. Probably not much of an option if you are at a large hub, but just resolved a lost luggage situation by going back to the airport. Flew YYC-YUL, and missed connection to ZBF (small town) but picked up bags as the flight was cancelled for days. Got a new ticket from YUL-YYZ-YQM. Missed YQM connection and overnighted in Toronto but bags were not at baggage claim, and they said they would automatically be retagged. Got reticketed from YYZ-YFC (so another change in airport). On arrival to YFC, no bags came off. Next morning 3/4 bags were delivered and the 4th got stuck in "tracing continues, please check back later". Left it for 4 days, then drove to YQM. Lo and behold, bag was sitting in the back - agent went and checked and found it. So I think they are not proactively scanning it sometimes, and it was just sitting there. Not sure when they would have eventually scanned it.