For years when my cats lived an indoor outdoor life they all wore collars with their name and phone number attached. The thought of ever losing one and never knowing what happened always filled me with dread so I felt a lot more secure knowing they were identifiable. Anything can happen to a cat while you are at work so it makes sense if they get lost that at least if someone finds them you have a chance of being reunited. It happened to me when I was very young but on this occasion my dear cat had been run over on the road. I'd been called to a family crisis and when I got back she was missing. A kind lady had found her and rang to let me know which was only possible because of the collar and tag.Of course microchips are good too but a collar with a name tag is obvious and it's easy for someone to give you a call. The other advantage is that a collared cat obviously belongs to someone.