This preserves the type of local peer identity involved in a specific recorded IKE negotiation failure, per its description. It tells an admin what identity type this device had presented during the failed attempt, which matters when the failure reason is authentication-related and the admin needs to check whether the identity type itself was part of the problem. A failure entry showing an unexpected identity type alongside an authentication-failure reason would point toward an identity mismatch as the specific root cause of that attempt.