Here's another common novice writing mistake that aspiring authors make, and unfortunately many critique partners and beta-readers don't or can't catch, because they lack the reading experience necessary to see it: genre confusion.
My own MS fell in this category. It's a mystery in a fantasy setting. After doing quite a bit of reading, I decided I had fallen short of reader expectations, not of fantasies, but of mysteries, which have their own set of rules governing story structures (i.e. reader expectations).
Think of your MS this way: If you were to shelve it at the library, where would you want it to go?
I'd hope my MS would get shelved as a fantasy book. That's where I would want my story to sit on a bookshelf, so I have to meet those reader expectations first. But it still has to be a good mystery, because that's the literary device I've chosen to drive the plot. Unlike a lot of fantasy, it's not centered around a hero's journey, nor a coming-of-age story, although the MC does learn and grow. The mystery is the plot driver, so I have to meet at least some, if not all, of those reader expectations.
It is super-duper important to read, read, read widely, both in your genre and outside it. Then, when your MS doesn't quite fit -- and you know it, because you're thinking, "Gosh, I wish someone would just write a book like mine, so I could use it as a comparable in my query letter" -- you've got to go back to the MS and rewrite. It's hard to admit, but it's so important to catch this, as well as the next novice writing mistake I'll tackle, writing in the "right" voice.
The site offers a nifty clover-leafed graphic, and the text clearly sets out the need to choose one genre, above all else, and allow that to govern your story, while not neglecting the other genres your book may fall into.
And to make matters more complicated, there's been an explosion of genres in the last 25 years or so. Take my all time favorite by Ben H. Winters, Sense and Sensibility and Sea Monsters. It features sea monsters, an alternate reality in which the world's waters are poisoned against humanity, a sea witch (so ... magic), and advanced underwater technology, which all sounds like a sci-fi / fantasy mash up, right?
Except I'm not done yet. It ALSO has young women swooning over the wrong men, reserving judgement on the right men, and the text mirrors Jane's original style beautifully but uses those sea monsters (and the sea witch) to signal to modern readers (who otherwise would be clueless to Austen's exquisitely understated 1800s social cues): "FOR THE LOVE OF GOD, SOMETHING IMPORTANT'S HAPPENING HERE! PAY ATTENTION!"
What genre is this, you wonder?
Imagine my surprise to discover (recently) there's an entire "Fantasy of Manners" sub-genre, listed here.
I would've labeled Winters' work as a "delightful mash-up," but ... while I'm not a publisher, even I know that's not a spot on a bookshelf -- either in a store or in the library.
So you have to read, read, read, and perhaps, invest in a professional critique or two, with a few agents or publishers at a conference, because genres are only expanding. Get a consensus, then make a decision. Learn as much as you can until you feel you know the conventions and reader expectations and can write them into your own story. Because your story absolutely has to have them.
