Deleted member 42
First time authors often copy the latest fad (vampires, the Tudors, P&P rip-offs)
This is a sweeping generalization; moreover it has nothing to do with what publishers actually contract for.
If a commercial /trade publisher doesn't think a book will sell, the publisher doesn't publish it.
Moreover, the average "first time" author has already completed one or more books that they didn't sell.