What is the purpose of the Automatic Locking Smart Rule?

Hello, does anyone know the purpose of the Automatic Locking Smart Rule?

Thanks,

Looking at the syntax of the rule, it locks any currently unlocked document (but not news feeds) which has been read and hasn’t been modified for the last 30 days.

So, after you’ve run the rule, you won’t be able to edit or delete any of those documents by accident. I suppose it’s a form of archiving. It’s not something I’ve used myself, however.