It's meant to be the operator of the mail server, and is generally used for contacting the operator about problems with their mail setup. It's required to be available per RFC822.
How much that works out in practice is inconsistent. Most sysadmins will set it up in my experience, but it's not out of the question that it wouldn't exist. Some domains will just set up a catchall and it'll be directed to someone anyway. It varies.
https://www.w3.org/Protocols/rfc822/
How much that works out in practice is inconsistent. Most sysadmins will set it up in my experience, but it's not out of the question that it wouldn't exist. Some domains will just set up a catchall and it'll be directed to someone anyway. It varies.