I just flew my MIL on a Delta flight home a week ago. When she got to her destination, the side of her baggage was sliced down the side with her clothes hanging out.

Maybe it was a mistake, maybe it wasn't. However, do you think someone could have owned up to it at Delta?
Someone either had to unjam it from a machine, or someone slit it open. It was a clean cut all the way down.

I told her to complain right away at the airport. So, she did that. This is the great part. They told her to go home, unpack, bring it back the next day and they should fly it multiple states away to Pennsylvania where their "baggage repair" person will see if they can sew it. If they can't, she will get a bit less than 50% of of the new value of the suitcase.

I always try to complain right at the airport when something happens to my luggage.