As a writer, I've never had any desire to write a series or even a sequel. I'm happy to leave my characters alone after they've resolved whatever set of crises I tossed them through. Yet the shelves in the stores tell me readers must want more books about the same characters. Is it familiarity? Is it easier to slide back into a world you already know than to explore a new one? Or is it because it's easier to market series?
I'm even more intrigued because I don't especially like reading series either. I have, of course, but when I buy a book, whether it is part of a 3, 5, 11 book series is not something I take into consideration.
I'm wondering that if I want to make it, I have to think of a story big enough to span several books, or create a world that can be the setting for more than one story. The closest I come to series writing is sneaking little cameos from old characters into new books. I love doing that. You get a fresh perspective on the character, or see them older or younger than they might have been when they initially showed up. In Assignment 9 the love interest is actually a character from another book I wrote, Holding it Together. In Chasing the Taillights, the new friend Lucy makes at school is a character I first came up with for an unfinished book I tentatively called Coming Home. But reusing characters isn't the same thing as writing a series.
What do you think the appeal of series is? Do you write with the aim of creating one? Do you like slipping old characters into new books?