Airline passengers often assume the warm “hello” from flight attendants is simply polite, but it actually serves a critical safety purpose. Cabin crew are trained to evaluate each passenger as they board, using that moment to scan for potential safety concerns.

According to flight attendant and TikTok user @itsmekikooooo, that friendly greeting is part of a silent checklist. Flight attendants assess whether passengers appear intoxicated, visibly ill, or otherwise unfit to fly.

They also look for passengers who are physically fit, speak English, and are traveling alone—traits useful in an emergency, as such individuals may be asked to assist.

While some social media users shared experiences of flying while sick or intoxicated, others pointed out the contradiction of airports freely selling alcohol despite strict in-flight behavior policies.

If a passenger is deemed unfit to fly, they may be denied boarding. Though the process may seem subjective, it’s rooted in keeping everyone on board safe.

Cabin crews also play a big role in comfort. They can provide bottled water, hygiene kits, or activities for children—small gestures that can improve the flight experience.

Many passengers shared stories of attendants calming their anxiety or being kind to their pets, showing how these professionals do more than serve snacks.

As air travel becomes increasingly stressful, with delays and limited service from some airlines, the attentiveness and quick judgment of flight attendants stand out as vital. Their job begins the moment you step onto the plane—and their vigilance may be what ensures a safe and comfortable journey.