From the outside, working at a store seems easy. It's just a matter of scanning items, giving change, and stocking shelves. .. right? Wrong. Here are 19 things that only retail workers will understand.

1. Sweet customers turn sour.

All is going well, and you're bonding over how cute that sweater is that she's buying. Then she wants to use an expired coupon, and you tell her she can't. All hell breaks loose and suddenly she's plotting your death. 

2. The customer isn't always right.

The old mantra doesn't ring true when someone tries to return a blender that they clearly drove off a cliff and threw into a shark tank before letting their dog use it as a chew toy. 

3. Black Friday is one of life's most terrifying experiences. 

One day after Thanksgiving, when everyone claims they're thankful for what they have, they trample each other in a stampede while trying to obtain more useless stuff. Any retail worker who survives this day should be granted sainthood. 

4. Comfortable shoes are everything.

Standing all day and running from the stockroom to the register means you're more than happy to turn up to work in your grandma's sensible velcro shoes.  

5. Bathroom duty is enough to make you quit on the spot.

The bathroom at Toys R Us on a busy Saturday afternoon. Enough said.

6. Elderly mall walkers are the best.

They turn up every morning in their 90s wind suits and sweat bands, and you love them for it.

7. Bras double as wallets.

There's nothing more revolting than watching a woman reach deep into her bra to pull out a stack of money. And it comes out so...wet. 

8. Everyone's bad credit is blamed on you. 

Telling a customer their card has been declined spirals into a barrage of insults and claims that you must not know how to work the credit card machine.

9. ...And so is their poor time management.

Oh really? Your kid needs a pioneer costume by tomorrow morning and she's known about this for three weeks? Now you're mad at me? Oh hell naw. 

10. You're more cynical than you ever thought possible. 

You've seen the worst side of humanity, and it's delivered you to a dark place.

11. A post-work drink isn't optional. 

It's medicinal, because it keeps you sane. And mental health is important.

12. You're great at faking it.

You've mastered saying "have a nice day" when you don't mean it, and your fake smile can fool just about anyone.

13. Everyone seems to think you double as a maid. 

Customers have no problem letting their kids run around like animals, knocking everything off the shelves and letting you clean it up.

14. The same three songs on repeat are equivalent to torture.

Every store seems to have about three pop songs on loop, and at least one of them is Michael Buble. It's enough to make even the most stable of individuals pull their hair out in a fit of rage.

15. You're expected to get into the holiday spirit when it's 90 degrees outside. 

Apparently it's perfectly acceptable to bring out the Christmas decorations in the summer, which means you're expected to be full of holiday cheer while simultaneously celebrating the Fourth of July. 

16. Weekends mean nothing. 

Saturday and Sunday are the biggest days for shopping, which means your social life on those days is pretty much non-existent. 

17. ...And when you do go out, it's with others like you. 

You bond with other retail workers because of your similar schedules, but also because they get you. Hanging out with them (and complaining about that one customer from hell) is therapy. 

18. Your time doesn't matter.

They know you were two minutes away from locking the doors and turning out the lights. They don't care.

19. Your employee discount is a curse.

You spend most of your wages on things sold at your workplace, meaning you essentially work for free.