Do you know why flight attendants wait for us at the door when we board the plane?

As you board the plane and head to your seat, the crew at the door greets you with smiles and warmth. But why does this happen?

This is a way to gauge what kind of passenger you are. Flight attendants don't just greet you out of politeness, they also check to see if you're drunk or too sick to fly.

But that's not all. Through this moment, the crew is also assessing which passengers could be useful in case of an emergency. The people they could ask for help from in such a situation should have some special qualities.

So, the crew can ask for help from someone who has no mobility issues, speaks English, appears to be able to open the emergency door, or is traveling alone.

So when you board a plane and see the smiling faces of the crew, know that it's not just to welcome you – they're actually silently assessing whether you're okay to travel and who can come to their aid if the need arises.