What security lesson was learned from the Operation Bojinka incident?

The lesson learned from the Operation Bojinka incident emphasizes the critical importance of ensuring that all deboarded passengers either return to or reboard the aircraft. This incident highlighted vulnerabilities in pre-flight security processes and the potential for individuals to exploit situations where passengers left the aircraft. Ensuring that all passengers are accounted for helps to mitigate risks associated with security breaches and unauthorized access to the aircraft. This focus on managing passenger movements not only enhances overall security but also facilitates better tracking and accountability for any individuals who may pose a threat.

The other considerations related to restricting what passengers can carry or logistical operational changes such as delays or entertainment enhancements do not directly address the core security failures that were exposed by the Operation Bojinka plot, which predominantly revolved around passenger handling and surveillance.