admin cannot delete roles issue

https://www.ads-software.com/support/topic/missing-delete-role-functionality?replies=4#post-5213690

It is not the privileges issue. “Delete Role” button is shown when you have roles you may delete. While there is at least one user with that role, you may not delete it at User Role Editor. “Delete role” is just hidden as there are no roles to delete.
Take into account that deletion of standard WordPress user roles are prohibited at User Role Editor.