Losing interest in a series

I love series. Let's just put that out on the table right now.  I love following characters through their life's twists and turns, and gripping the book (or i-pad) anxiously as they each make choices that will change their lives forever. And mine. Because as I read, I think, "What would I do, if I were them?"

But what happens when the last book takes, oh say, three years to come out? I lose interest.

It's happened twice now, where a final book (for whatever reason) goes years before being released. That's a long time to hang off the edge of the cliff with a character, folks. My arms get a tad tired. So I let go and move onto to another character who will offer me closure.

Before you rail me for being unkind or hold it against me in the future (should I be said author who takes three years to finish) I devoured Robert Jordan's (c/o Brandon Sanderson-bless you) most recent Wheel of Time books the moment they hit the shelves. Partly because I was FAR too invested in the story, and also because in anticipation of the release I started rereading the series and became RE-invested.

AND in the case of the other books? I did buy the last books of those series when they came out. I just haven't read them yet. I'm not interested enough...yet. And folks, these were wonderful stories to begin with. But there is only so much time I can wait before I begin to think, "Was that last one the end of the story and I just missed it?"

I love what Elana Johnson has done with her series to keep us in the groove while waiting for SURRENDER. All her short stories, peeks, artwork, etc., really bridged the time gap and made it seem like a blink of an eye before the next book was released. Well done, Elana! Well done.

I've heard various suggestions via the writing community that say, "Don't write your series before you get your first book published." Hogwash. Sure the plot may change a bit, because your editor may have significant changes for you, but think about the anxious reader waiting for your next book and what you might be accomplishing ahead of time to keep their interest (aside of writing a great story). Timing is key in an industry that has so many wonderful characters to offer. If you don't.

Because if you leave your characters hanging off a cliff too long? Well, better hope they've got really strong arms. It could be a while before I get them down out of my head.

So what makes you lose interest in a series? What could writers be doing to keep you more invested?