Shopping always means playing a game of size roulette. Every time I find a new pair of pants, I have to stand in front of the mirror and place them in front of my legs and then try to imagine whether or not there's enough space to expand once I squeeze in my ass. I've been a 4, 6, and 8, all in the same store. You can't help but wonder why people freak out so much about sizes when they seem so insanely arbitrary.

Well now this video by Vox proves that it's not just you. Sizes are whack.

For example, people like to say that Marilyn Monroe was "fat" (snort) because she was a size 12, even though her body measurements were an itty-bitty 36-24-34. That means she'd probably be a size 8 at Topshop, a 6 at Zara, and a 4 to 6 at American Apparel.

To test the discrepancy out for herself, Vox reporter Dion Lee bought a pair of size 4 jeans at three different clothing stores and tested them out. Sure enough, only one pair fit.

So what's the deal? Well, the video above walks you through the whole complex history of clothing sizes, which includes sizes being invented for men's Army uniforms (and thus totally nonsensical for women's clothes), a misguided study of women's sizing that only included white women, and an original sizing chart that set sizes from 8 to 42 and was withdrawn in 1983 because it was just that bad.

Vox

Since 1983, companies started to label clothing in smaller sizes as a marketing ploy. That's why Marilyn Monroe was a size 12 back in her day but would be a 4 to 8 now. It's called "vanity sizing," i.e. artificially lowering the size on a label in order to woo someone into buying the item.

So now, retailers are choosing a specific group of women and tailoring their clothing sizes to that demographic as opposed to women in general. Which is why a size 4 in Abercrombie & Fitch can fit like a size 0 in Guess.

"It's not you, it's the industry," said Lynn Boorady, associate professor and chair of fashion and textile technology at Buffalo State University. "Women's bodies are fine the way they are. They're just random numbers. They don't mean anything. And if you don't like the size, just cut it out of your clothes."

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