The English language is so funny and stupid and clearly cobbled together poorly from many different languages like some janky ass open source project.
Like, for example: we use apostrophe-s to indicate ownership in 99.99% of cases. "Pendell's Cohost Page" you know, the apostrophe-s indicates it is my Cohost page. And this is how apostrophe-s works in just about all of English.
Except for it's. Because the word "it's" uses the apostrophe to contract two words, "it is." Well, okay, we can't just interchangeably use "it's" for both purposes, that'd get confusing real quick! So to indicate ownership in this case, where the owner is an "it" you use "its."
Some last-minute hacky patch note type shit. "Uhhh, FUCK, Bob, that rule doesn't work for it's, it hangs the whole system." "Well shit... Make it 'its' then." "But that breaks the rule that's supposed to be consistent--" "DO YOU HAVE A BETTER IDEA JON? IT'S ALREADY LIVE AND WE NEED A PATCH ASAP, THE TICKETS ARE STILL FLOODING IN." So they issue the patch and then never go back to devise a better solution.
What do you mean English is the hardest language to learn?