http://www.telegraph.co.uk/travel/trave ... table.html




So how will we know that this rare or an everyday occurrence?

I've always assumed that after you've checked in that the bag was handled by the airport and not the airline. If that is the case then perhaps we should be getting league tables for airports in addition to or instead of airlines.

It depends. At major hubs airlines have their own staff, (eg BA at Heathrow) but at others they'll use a service company that serves several airlines at that airport.
Sure, modern airports use high tech systems that can remove the human element, but a lot of airports still do a lot of stuff by hand.