I know many people here do not check bags but this is for those who do.
Some people think it is an identity-fraud or safety issue to have complete ID info on a bag tag affixed to the outside of luggage. (Safety issue because one's visible address could fall into the hands of a stalker). But it is important to have some form of contact info---email address or phone number) easily accessible on your checked bag, in case it goes astray. This happened to us last week, returning home on a domestic flight. We can check bags for free on Alaska Airlines and we do.
We were on the light-rail into Seattle from the airport when my husband noticed something odd about his bag. He first thought his bag must have been inspected by TSA and they attached a different bag tag, but I took a closer look and noticed a slightly different color on one part of the bag---only apparent on close inspection in good light. This is an Osprey Ozone which has a distinctive shape and look, and is fairly uncommon. It was not his bag.
Fortunately the bag had a name tag with phone number. When we got off the train he called and reached the party. They had not yet realized they had picked up the wrong bag as they were in the car driving to Issaquah (east of Seattle). We arranged to meet at a Park and Ride which was right on their way to exchange bags. They apologized profusely, as they had picked up the wrong bag before we even got to the carousel. The Osprey bag my husband grabbed was the only one left, so he did not confirm that it was his at the time. ( If he had, the only difference would have been an earlier call to the other party).
Bottom line---make sure your phone number is on your bag, AND check the ID before you walk away from the carousel. (Some say the ID and number should be inside your bag, but I prefer not to have someone else opening my luggage to find it).