Life happens. You create a great contact List. And do a great Report on it. And then, you … move on hopefully to greener pastures.
Your legacy is left behind as Deactivated User. There is no owner! It is awkward to people to use anything owned by a Deactivated User. It is a liability among other negative things.
Hubspot gods should be able to move the ownership of Lists and Reports from one user to another.