Requiring local network access for the default Admin User account is a targeted measure to prevent unauthorized access from unfamiliar IP addresses, particularly those originating from outside the organization's network. This approach ensures that only devices physically connected to or authenticated within the local network can attempt to use the Admin User account, significantly reducing the risk of external attacks. Increasing password complexity and restricting simultaneous log-ins are good practices but do not directly address the issue of access from unfamiliar IPs. System hardening is broader and not specifically focused on the Admin User account issue.