Why is its possessive form without an apostrophe, when it’s opposite of other English rules and often counter-intuitive?

Question

See this headline: proper usage, but difficult to parse. “It’s” = “it is”, exclusively. The origin of this “exception” rule?

In: 6

Answer 1

“Its” when used as a possessive isn’t a proper noun and requires no apostrophe just like his, hers, or theirs. “It’s” is a contraction of “it is” requiring an apostrophe.