Take Harry Potter for instance. J K Rowling really hit the jackpot with that series. It's earned about £1 billion or so they say. I'm told she started writing them about ten years before the first one was published. I can't see where the clever view of the future market came in here. She just wrote the things she wanted to write. It was the public that decided to like them.
The Fifty Shades of Grey phenomenon did give rise to some steamy derivatives which sold in vast numbers. But the market for romantic fiction is well established. Mills and Boon, for example, have kept it provided for years. Fifty Shades was, like Harry Potter, a bit special but not out of the ordinary in terms of market sector. Similarly, Dan Brown's books sell in their millions but are part of a mainstream genre with a huge established readership. There's nothing unique about any of these books other than the amount they sell.
So how does that help a poor writer who is trying to find a market? Is there a niche somewhere that hasn't been filled?
I don't think so.
Being derivative, in other words taking someone else's theme and trying to do a variation of your own, isn't going to work. I once wrote a humorous science fiction novel. The response I received was along the lines that they had Terry Pratchett for this kind of thing, he does it a lot better and, what's more important, he has a loyal readership. I would have to be either better or different and I was neither.
What I mean is that you shouldn't set out to be a second rate Rowling, a E L James lookalike or a Dan Brown clone. People already have the real thing to read, they don't need you to give them something similar and slightly inferior.
There's another reason for not writing something just because you think it might sell. By the time you've written it another trend will have taken over. You'll be old hat.
So, write what comes up for you, what has energy for you, what feels right for you. By all means imagine you are writing for someone else but make this a specific person rather than a statistical demographic.
What people like to buy are good books. Books that are written with heart, carefully edited, professionally produced and gently offered for their appreciation.
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