What happens to shipments with incomplete or improper documentation?

Shipments with incomplete or improper documentation are classified as frustrated cargo. This means that they cannot be processed or moved until the necessary documentation is provided to ensure compliance with regulations and procedures. Frustrated cargo often involves issues such as missing paperwork, incorrect information, or failure to meet customs requirements, which can hinder the shipment's delivery process.

In this case, "frustrated" describes the state of shipments that cannot be advanced due to documentation issues, which is critical for logistical management in air freight operations. This ensures that all shipments are legally compliant and maintain aviation safety and security protocols. The other options do not accurately reflect the typical actions taken when documentation is not complete or proper.