The water would fall off the earth
We wouldn't be able to rotate around the sun properly
-Flat Earthers generally believe in a barrier, be it an ice wall or a dome.
-They generally all believe that the sun is actually small and moves over the flat Earth. Earth doesn't rotate around the sun.
I've watched and talked to plenty of flat Earthers and it's pretty much the ultimate conclusion of conspiracy theory belief. They all tend to believe every other conspiracy theory; fake moon lands, false flag mass shootings, 9/11 was an inside job, gouvernement engineered Mandela effect, climate change is a hoax, the holocaust didn't happen, anti-vax, chlorine in the water is poison, chemtrails, the world is ran by a shadow organisation (generally the the Masons, sometimes the Jews)...
You'd think most flat Earthers would be religious and whilst a good few are and base it off what's in the Bible, a load actually support their belief with an extreme distrust of the government and established knowledge. Essentially everything is a lie, if we're taught something as common knowledge but you can't see it yourself with a cursory glance, then it must be questioned as is no doubt a falsehood pushed by "the elite".
It's a form of delusional disorder, the actual believers are mentally ill and you can always count on people like Mark Sargent to cash in on the victims. This guy knows is all BS but it's his claim to fame and makes him the big bucks:
He should explain the horizon first.