Awhile back, an author asked if the editor will catch and correct inaccuracies.
The best answer is no. Or a maybe.
Fact-checking isn’t necessarily an editor’s job. Editing is their job. No author has a right to expect an editor to know every detail about every topic to make a story or nonfiction book accurate.
For example, did you know that today is (among other celebrations) Thank You for Libraries Day? (See April 21 Holidays and Observances, Events, History, Recipe & More! (holidays-and-observances.com.)
A writer mentioning the day as falling on April 22 instead of April 21 should not expect any editor to catch this error. Granted, since most books go through several editors, a writer may happen upon at least one editor curious enough to check this out (ha ha). However, no writer should count on an editor to correct mistakes.
At least one reader may catch the writer’s error, and the writer is sure to hear about it. The editor may or may not be forgiving. They’ll be coping with the extra work of responding to an inaccuracy instead of reading glowing reviews about the book. Dozens of factual errors may add to the editor’s degree of aggravation, and they may decide not to contract with that writer again.
So why don’t publishers help the writer out by hiring fact-checkers? Here is a brief article from Psychology Today to demonstrate the work involved: Why Publishers Don’t Fact-Check Books | Psychology Today
Bottom line? A writer who isn’t an expert on a topic needs to become an authority before crafting a book on the subject. Knowledge is only one part of the author’s job.