It’s more of a consensus, than a rule. It’s only obvious because of the way we phrase it and the consensus to use that symbol. But we could’ve just as well settled on something like “x follows y” or whatever and you’d have an arrow pointing at the bigger number. Or any other number of ways to compare without using that symbol exactly. It’s more a language than anything, really. What’s important is that everyone understands the same thing regardless of what symbol we use. That’s why everyone uses it like that, not because it’s obvious.
It’s more of a consensus, than a rule. It’s only obvious because of the way we phrase it and the consensus to use that symbol. But we could’ve just as well settled on something like “x follows y” or whatever and you’d have an arrow pointing at the bigger number. Or any other number of ways to compare without using that symbol exactly. It’s more a language than anything, really. What’s important is that everyone understands the same thing regardless of what symbol we use. That’s why everyone uses it like that, not because it’s obvious.