You write a book. The first time is probably a draft and all you probably think about is getting the story that’s in your head out and onto paper. (Computer screen, whatever.)
Then, hopefully, you take a break. Take a step back. When you’ve gained some perspective, you go back. You read. You revise. You edit. You polish.
You know the drill.
At some point in this process, you need to consider your audience. To be particular, most writers think about their primary audience. Basically, it works like this. You write a book you intend to publish, and you face the fact that publishing revolves around genres and specific genres have specific followings (readers who read books of that genre). You, like most every other writer, must find your readers (primary audience) among the followers of the genre your book falls into.
Yes, I know, many writers find these genres far too rigid and some don’t like anyone to place their book in any kind of genre. (BTW, from a marketing perspective, that kind of snobbery is completely self-defeating—just saying.) So, writers and readers develop sub-genres, cross-genres, and other ways to push the envelope. It can become pretty complex.
But, when everything is said and done, when everybody gets all that resistance out of their system, the buying market (i.e. people who buy books) effectively forces people to categorize a book—whether nonfiction or fiction—because that’s how books get found by potential readers. If someone totally and completely and successfully resists such categorization, then their books don’t sell, unless you somehow manage to reach out to potential readers individually. (Speakers who sell their books exclusively at conferences and through other direct-selling avenues do this, but their primary occupation is speaker not writer.)
So, you’re revising, editing, and crafting your book. To do so effectively, you have to consider your (primary) audience. What do they expect? Will giving them what they expect satisfy or dissatisfy them? What rules must you follow? What rules can you bend? What rules can you break? The answers to all these questions factor into your final product, and it’s often better done at a conscious level (versus a subconscious level), especially if you are writing outside your own dominant genre (the genre you have read from most and have enjoyed the most throughout your life).
Most writers know this. A good portion of those writers actually accept it. Those who are published by traditional publishers learn how to work it to their advantage.
But a primary audience isn’t your only audience. Most books that sell really well have more than one audience.
Consider the Harry Potter books. The primary audience of those books consists of children. Yet, how many adults (a secondary audience) have read those books, too? Lots! It’s even possible that more adults have read the books than children. Think about it a little more, though. The primary audience is children who enjoy fantasy. The secondary audience is adults who enjoy fantasy. Yet, there are both children and adults who had never read a book within the fantasy genre (at least, not on purpose) who enjoyed the Harry Potter books, too. Those are tertiary audiences.
I cannot tell you to what extent audience was considered in writing those books, but audience was certainly considered in the marketing of those books.
That brings us to the topic of a purchasing audience. Some books are purchased by the people who are expected to read them. Other books are purchased by someone who expects someone else to read them. Whether your book fits primarily in the first or the second category, you will also fit secondarily in the other category. This means that if you expect readers to be the ones purchasing your books, then people who do not intend to read the book will also likely purchase the book for readers. This also means that if you expect others to purchase your books for readers, then people will also be purchasing the books for themselves.
As you come to the finish of your revisions, crafting, editing, and polishing, take a moment to consider your purchasing audiences. What will help make that sale? What will deter them from making that sale? Is your book really ready?
See, the thing of it is, if you’re writing to be published, to be sold, then you do have to think about these things. The answers to these questions do not have to drive what you write. I’m not talking about “selling out” here. I’m talking about “selling in.” Stay true to your material, always. But do consider what your audiences are looking for and how giving them what they want can make your story even better.