Edit: Thanks for taking the time out to reply. I’m enjoying reading all the different explanations and view points.
In: Other
So most bags are loaded in to cans (ULD’s) which are designed to be efficiently loaded into aircraft. The can is built by computers and robots who know where every bag is (fully tracked) heavy bags go at the bottom that sort of thing.
The cans are pre-staged at gate ready to be loaded as part of a slick turn around.
Then – the aircraft parks at the wrong terminal / gate – and now hundreds of bags need to be quickly moved.
Or while you think your travelling with your bag in could be in the hold of another aircraft going to the same destination.
Or someone on who check in and checked in their bags didn’t get on the flight this causes a bum (bag unload message) and now to derisk the unaccompanied bags is unloaded.
But that will require the can be unloaded and the heavy bag at the bottom of the can being found and pulled, often the whole can is late.
Or well the check in desks have rigid inputs so you can’t check bags to destinations which are not operating. But suppose your flight is late or there is an operating issue then the admins turn up, they can check in any bag to any destination and if they make a typo the tickets are produced which are invalid.
Then there is the bag which falls off the conveyor, the twits who wrap their bags in cling film.
The twits who try and put balling balls which are rapped in bubble wrap, and l manor of out of gauge items which slow down the process.
Lots go right and that’s what’s expected but the sort computers can go wrong, IDs can be overwritten, messages can be lost, it’s not a perfect system.
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