Showing possession is, in most cases, simple enough. For a singular noun, you add an apostrophe and an
s (as in "the horse's mouth"). For plural nouns, a single apostrophe (the bakers' convention).
All very straightforward. Except for the exceptions, of course.
One exception relates to plural nouns that don't end with an s (children's, women's, etc.), not a problem for most people.
Then there are nouns that are plural in form but singular in meaning (politics' shortcomings) and, similarly, names of organizations or places that end in an s even though the entity is singular (United States' policies).
My problem with possessives arises when the word ends in an s that is pronounced. I prefer adding an apostrophe and an s so the word becomes, for example, "Dallas's" as in "Dallas's population is growing." But my experience with publishers is that they prefer to omit the possessive s on all words ending in s so that the sentence would become "Dallas' population is growing."
I assume the publishers prefer to be consistent rather than worrying about whether the s is pronounced or not, and if you sign a contract with a publisher that uses this particular style, well, you have to accept their style.
But they'll never make me like it.