FortiGate hardening is not one setting. It is a collection of small decisions across administrative access, interfaces, authentication, logging, services, VPNs, policies, and objects. Weakness in one area can make the whole appliance harder to defend.
Common review areas include exposed administrative interfaces, weak or shared admin accounts, missing MFA, permissive trusted hosts, risky local-in services, incomplete logging, outdated policies, and broad VPN or firewall access rules.
Because these checks span different parts of the configuration, they are easy to miss during a rushed manual review. Structured auditing gives engineers a more consistent way to find hardening gaps and document what needs to change.