Hello there @Jay91!
The user can self-delete account if:
-
1 post or less
and
-
their account is less than a few days old
This setting kicks in on post number 2. You can self-delete if you have 0 or 1 posts. This self-delete option is right at the bottom of their user preferences page.
If you are forum admin, you may change this setting via delete_all_posts_max and delete user max post age.
Hope this helped