When you board a plane to jet off on holiday, you get greeted by a member of the cabin crew.

Smiley, positive and immaculately dressed – they're always there to say hello and relax as we enter the plane. But, it turns out, their job is a lot more important than being polite.

While flight attendants are there to look after passengers, serve food and drink and ensure we have a safe flight – they're also there for another important reason.

Little you may know, they've actually been judging us all along. A video has gone viral on TikTok after a user, known as MrsMiva, revealed a super big secret.

Being a stewardess herself, she knows all the tricks of the trade, and she recently revealed why the cabin crew host a meet and greet when we board planes.

Over the clip of herself, she wrote: "Did you know that your flight attendant greets you not only out of politeness, but also to check whether you are too drunk or sick to fly?"

The post has been liked over a million times, and it's left thousands of people gobsmacked. Many people didn't realise they were being checked as they boarded the plane. Sneaky!

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One person was stunned, writing: "Wait, is there a reason why they always ask me where I sit when I go onboard?" Another added: "To see if you're 1. Safe to fly (not intoxicated) and to see if you could help in an emergency."

A third replied: "And looking for suspicious behaviour." Meanwhile, a fourth commented: "We are also picking out good candidates in the event of an emergency."

Some people even shared their own experiences to back the theory up, with one writing: "I was denied an international flight from England to America because they thought I'd die en route from being so sick." And another chirped in with: "True, and it's the toughest part of the day. Without being paid!"

Not everyone was so convinced with the idea though, and they couldn't resist cracking a few jokes. One even said they thought cabin crew were nice to them, because they're so "cute and cosy".

One chimed in with: "No they greet me because they like me." Another said: "No they say hi because I'm super cool and awesome - that's why." A third also added: "No - it's because they think I'm super pretty." There were many more people who shared similar thoughts too.

More often than not your flight attendant will greet you in a friendly and welcoming manner when you board an airplane. Usually, they will say something like "welcome aboard" or "good morning/afternoon/evening", while giving a breaming smile.

Let's be honest, whatever the reason they do it, it's always great that they're super nice. It helps to make us comfortable and relaxed before take-off.