This is a topic that doesn't come up very often in general writing conversation, and it has several different aspects to it. Often, it's published writers who talk about it, and unpublished writers don't want to hear that after your first book is accepted, printed and out there, it doesn't all magically fall into place and become easy. I've heard it said many times: Getting published doesn't solve all of your problems, it just gives you a new set of problems!
I was reminded of this when reading Cynthia Leitich-Smith's blog today. As she is celebrating ten years of her website, she has been asking writers the question - Over the past decade, what are the most important lessons you've learned about your craft, the writing/artistic life, and/or publishing, and why?
Today's answer was from Nancy Garden, and among other wise and helpful things, she said: I think the most important lesson I've learned about my craft--or at least about myself as a writer--over the past decade is to slow down!
By that I don't necessarily mean to write less, and I certainly don't mean to take more time off (what's that?), but what I do mean is to be sure to give each new book or story all the time it needs before sending it off to one's editor or one's agent.
This is one of those aspects of 'the next book' - the feeling that, once you have one run on the board, you have to keep producing those books at a good rate, and not let a time gap open up. After all, you're building a reputation, a publishing track record, and if you take too long, publishers will forget who you are. But as Nancy says, handing over an under-cooked book won't do you any favours either. You have be sure every book is the best you can possibly make it. I always feel my next book has to be better than my last one. Maybe not always possible, but good to aim for. And it does take time.
Another aspect of this is genuine pressure from the publisher when your next book is part of a series or trilogy. I heard a fantasy writer say once that her first book took ten years. No one was waiting for it, and she could re-work it to her heart's content with no one looking over her shoulder. When it was accepted, suddenly the second one had to be finished within a year, and when she looked at her draft of it, she realised nearly everything had to be thrown out. To get it in on deadline, she spent many, many nights and weekends on it, always conscious that it was "expected" by someone. Sometimes that kind of pressure can cause major writer's block!
Series are similar, but different. Because you are faced with not just one more book, but maybe four or six or ten. What happens if you get to Book 4 and decide you now hate your main character? Or that the original series concept bores you to death? Sometimes a publisher will put impossible deadlines on you, in order to get the series established in the market. How would you feel about writing four books in eight months? What if you make your name with a series but desperately want to write 'the book of your heart' and the publisher says No?
There is an up-side to this, of course. Expectation of the next book can fill you with confidence, while the first book filled you with the fear that no one would ever want it. A contract does wonders for making you feel justified (especially to scoffing family) about all that time and energy you spend on writing. A solid series concept can make you feel more secure about writing the next one and the next one, because you've done all the hard groundwork and you know what you want to do with it. However, these days the next book is never 100% guaranteed to be published, so at least make sure you get some money up front!