My luggage was missing when I landed at KIX.
But it wasn't the airport's fault - my luggage was still in Amsterdam.
Arrived <24 hours later and they delivered it to my hotel in Osaka.
I once had SAS lose my luggage on a direct flight from Copenhagen to Tokyo Haneda. I was sure that such a thing was impossible, but I learned an important lesson that day.
In my experience, that's far and away the most common scenario. Luggage misses a connection, doesn't get on a flight that has ben changed because of weather, or otherwise ends up somewhere it's not supposed to be. Many airline tracking systems are better than they used to be but AirTags or equivalent are not a bad idea.