They’re Sizing You Up As You Board
It is always reassuring to see your flight attendants greeting you as you enter the plane. Of course, it’s excellent customer service, but they actually have a hidden motive to do so. They are judging you in secret …

When passengers enter the aircraft, flight attendants quickly make important assessments in just a few seconds. They examine each passenger and mentally note those who may be problematic or intoxicated, they notice those who are travelling alone or those who may need extra assistance, for example when they are disabled or travelling with children. They also see who is strong and could be helpful in an emergency.