This expression is mostly from social media (specifically Tiktok). Rule number one is "cars are better than people." Mostly used by car people/Motorsport fans.
"No way, he cheated on you? Hop in my car, and never forget rule number one"

"I'm always prioritising rule number one, that's why I never date anyone."
by Sunaarin August 4, 2023
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Don’t do it over the phone, social media, etc., because you don’t make a connection with the person even if you know a lot about them.
Dude 1: dude I met a girl
Dude 2: how’d you meet
Dude 1: we met over Instagram

Dude 2: seriously dude, remember the number one rule of dating, don’t do it over your phone
Dude 1: shit I forgot, I’ll tell her
by DeanGullberry69 February 6, 2021
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