We did have one incident, on our flight from JoBurg through to Kigali when checking in our luggage the desk noted that my daypack could come loose from my travel pack, I said no it’s attached in 4 places, but then I decided to padlock it. Glad I did as when we got to Kigali someone had tried to open it (don’t know if in Kigali or JoBurg)
My husband wasn’t so lucky, we thought he only had clothes in his bag so weren’t worried about locking it but forgot about our travel speaker. Someone had gone right to the bottom of his attached daypack and stolen the speaker out of the box. The daypack was open when we picked it up off the conveyor belt. Really annoying as it was brand new. We complained to South African airlines but they haven’t deigned to respond.
I think the moral of the story is when the luggage attendant drops hints that your bag isn’t secure, make sure you listen.