Single or Series?

There's a reason I have two full bookshelves and am working on a third: I read a lot of series.  Looking at my main bookshelf, I'd say 75-80% of the books on it are parts of a trilogy or more, including the ones where I only have part one because the rest of the series hasn't been published yet.

Some of these books are so thick that one volume is longer than entire trilogies.  I like big books and I cannot lie.*

So naturally, this leads me to think of how this affects my writing.  I've talked before about how I don't like writing short stories - I have real trouble coming up with ideas that I can fully express and do justice to in a few thousand words.  Granted, I did have one short story published, but that was ~7500 words, which is pretty long for what's considered a short story.  The only stories shorter than that I've written and thought were good enough to share were all fanfic.

Oh, like you've never written fanfic.  Don't look at me like that.

Thanks to this, when it comes time to plot, I often have to force myself to focus on just one book.  THE ACCIDENTAL WARLOCK was going to be the first of a trilogy.  There was even a time when I had grandiose plans to not only write three different series spanning three different worlds within a multiverse, but to bring all three of those series together in this amazing trilogy where everyone got to meet and take down some threat that had significance behind the scenes in all three series.  I dubbed the plotting document for this "THE EVERYTHING PLAN" - yes, I used all caps - and it's been gathering dust on my hard drive for over two years.

So it's safe to say that big plans don't always pan out.  Yet I very rarely have a story idea that will be just one book. Even when I'm working on something and I honestly don't know what the second book would involve, I'm still thinking ahead, considering what it could be.  I generally think this is a good thing, but it does have me wondering if I'll ever write a novel and have no intent of visiting that world or those characters again.

Granted, I could blow up the world at the end to make sure that happens, but that seems a bit drastic.

I know that I'm not supposed to think about the publishing attempt stage for books I haven't written yet, but it's hard not to, when I find myself thinking ahead.  Will it be easier to sell a book when I can say it's going to be part of a series?  I know no one can count on getting a multi-book contract right from the start, so that's something to keep in mind.  Is it better to just say that I have sequels planned, and be ready with them if the best happens?  That was my intent with TAW, but the less said about that right now, the better.

This is all just speculation, of course, but with three series I really enjoy having new books coming out in January (all on the same day, how awesome is that?), it got me thinking.  So, what about the rest of you?  Do you prefer your books one-shot, or do you like series?  How long can a series go before you lose interest?  Do you plan to write one-shot books, series, both, or something else?  And am I the only one who loves hearing that a series by a favorite author will be really, really long?  Dresden Files and Stormlight Archive, I'm looking at you . . . and eagerly awaiting the next volumes.  Bwa ha ha.


*Yes, this entire entry was an excuse to use that line.