Five years after my debut as a novelist, I contacted other writers who'd debuted the same year to find out where they were in their journey, how publication had and had not changed their lives, and so forth. I wrote an article about my findings, which I pitched to several writers' publications ... but I found no takers.
It surprised me, because once I had my first book deal, my main questions were about what might happen next, what would happen next, and how one might go about building on that first book. What were the odds and what were the options? I think writers' resources (magazines, conferences, etc.) are great in helping writers to first publication, and they provide ongoing support for career writers. But I'm not so sure about the bridge from the first phase to the second phase.
In any case, now it's been closer to ten years, and I've seen stories unfold even more. Back when I got my first book contract, Borders and Barnes & Noble were the big chain bookstores, Penguin and Random House were two separate publishers, ebooks were so new that contracts didn't always cover them, and self-publishing through Amazon was not a phenomenon yet. So much has happened--including the recession of 2008, which dealt blows to the industry that I think are still underestimated.
In ten years I've seen many writers go on to publish multiple books--some in the same genre in which they started out, some in different genres. People have tried out or wholeheartedly embraced self-publishing; they've found careers in editing, agenting, ghostwriting. Some are writing under pen names, some under multiple pen names.
But there are those who didn't publish again, as far as I can tell, or who didn't continue publishing. On the cusp of my debut, I used to think of this as a horrible fate, to be dreaded and avoided at all costs. What I didn't realize then was that disappearing from bookshelves doesn't mean disappearing from life. Many writers turn to other art forms, or they delve into new careers, or devote more time to family. And the thing about publishing is that you never know when a new project will strike--so much is possible. The track is not as narrow as I used to fear.
So for the debut authors out there who might worry about what happens next, I would say: A variety of things can happen, and there is no one thing that must happen in order for this to be a success. There are many, many paths.