The author Julian Gough writes today in the Guardian that Amazon’s short Kindle Singles are the future of publishing. By this, he means that the optimal size demanded by publishers (from about 80,000 words to–I’m guessing–150,000) has been established as the norm because books need to look value for money but cannot be practically bound at ginormous sizes.
I agree. One of the most effective books I read over the last couple of years is True Grit. It was marketed as a novel but, really, it’s novella length. There have been a few occasions when, reading a book, I’ve got the impression that a subplot has been added to increase its bulk. Now, that’s not necessarily a bad thing, and if a book needs work like that a careful editor can suggest it to an author, but I think you need to think twice before inserting material willy-nilly.
I wanted to add this: Shorter works give writers the opportunity for a faster turnaround, the opportunity for which is not to be underestimated.