in front of my computer-- where I write most everything
What makes someone an author is another of those things people ask. Author has more than one meaning. You can be the author of a new idea and not have written a single word. But if we take the word author and combine it with words-- it'd be someone who wrote an original work.
Not everyone needs to give themselves a title. Many don't care whether they are regarded as an author or a writer. They do what they do, and titles be damned. But if someone needs a title to identify themselves, which our society can request multiple places, what would make them an author?
The same debate can be made over painters or photographers. I love taking photos and enjoy painting; but if I was identifying myself to someone else, I'd not call myself a painter or a photographer. What would it take to bring me to the place where I would?
Authors might feel secure in deeming themselves such, if a big publishing house bought their book. That would mean they had been taken seriously by someone in the business. It is about the only reason I can see anybody would want to sign a contract for their book because those contracts limit the writer's rights-- for a very long time. Big publishing houses also take part of the profit from each sale. They often don't advertise anybody but their biggest writers. What they do offer is that cachet of saying you signed a contract with them. By the way, if you have yet to bring out your first book, be very careful that that desire for a publishing house doesn't lead you into one of the vanity presses, which can make your book so costly that it won't be purchased and limit also your rights for future independent action.
Does being an author require bringing out more than one successful book? If that was so, Harper Lee was not an author. Does that sound right to anyone? The new book coming out by her was actually written before To Kill a Mockingbird and from it came the masterpiece due to an editor's suggestions to take another look at how Mockingbird was told. So the new book is a sequel that actually was written first but forgotten.
Lee is not the only author of works regarded as masterpieces who only published one book. Did she remain a writer all of her life? Good question as she is rather private, and I am not sure who knows the answer to that one.