As a string of other embarrassing breaches earlier, if it is not a deliberate attempt to circumvent airport security, The most probable cause for the incident arose may be like this scenario: “A man in a dark blue jacket, jeans, and black backpack walked through an exit lane in a hurry without realizing any warning sign, “fortunately" he past a TSA screener, who failed to make eye contact with him. or distracted by talking to another passenger asking for direction. In other words, what may occurred is just someone went in the out door. As an airport operator, one of the purposes is to be responsible for the operation and keep it safe down there, is one of the main purposes for managing the airport. So that’s definitely a dereliction of duty. The security is largely depends on the personnel, it is critical that every employee was trained to focus on their own job, they need to be on guard especially at such an vulnerable area, which is also very important to the departure lounge but people rarely will pay attention to, if few staff can not hold the whole situation, place more TSA agents there in case of the emergency, it works better than getting the cameras, alarms, or screenings installed. The contingency plan should always being ready to be carried out rapidly at any time to keep the airport and terminal running as normally as possible so that there will not be a large amount of delayed flights after the incidents happening. Once the illegal breach occurred, it have to be reported directly to all the departments concerned. the first priority is to turn off the moving walkway in order to avoid further hurts, the securities are expected to take efficient action to keep the order among the chaos, active the alarm immediately, in the meanwhile, an announcement is making over the public address system to let them