Airline passengers often assume that the cheerful “hello” from flight attendants is just good manners, but it turns out there’s a deeper reason behind the friendly greeting. Cabin crew are actually trained to assess each traveler as they board, using that moment to quickly evaluate if anyone poses a potential safety concern.

According to TikTok user @itsmekikooooo, a flight attendant with over 500,000 followers, that warm welcome is part of a silent checklist. They’re scanning for passengers who might be too intoxicated, visibly ill, or otherwise unfit to fly—essentially identifying anyone who could become a liability mid-air.

Flight attendants also look for individuals who appear physically fit, speak English, and are traveling alone, as these passengers might be asked to assist in an emergency. While some social media users agreed, sharing stories of slipping past detection despite being sick or intoxicated, others questioned the process, pointing out the contradiction of airport bars selling alcohol freely while airlines crack down on drunken behavior onboard.

Some even asked what happens if a passenger is deemed unfit to fly. Despite the skepticism, most acknowledged the professionalism of cabin crews and the mental load they carry. Many used the opportunity to share unrelated fears or experiences, including how attendants soothed their anxiety or interacted sweetly with their pets. Beyond safety, cabin crew can also make flights more pleasant in practical ways—passengers can ask for small comforts like bottled water, hygiene kits, or activity books for children.

But as flying becomes increasingly inconvenient with delayed or canceled flights, limited perks, and poor customer service from certain airlines like Spirit, United, AirCanada, and AirFrance, the small efforts of attentive cabin crew stand out even more. Their responsibilities go far beyond serving snacks, and their observant nature starts the moment you step onto the plane.