Every book that never got finished was, at some point, going well.
That's the part nobody talks about. The abandoned manuscripts sitting in desk drawers and forgotten Google Docs folders, they all had momentum once. The writer was excited. The pages were coming. The story felt alive in that way where you think about it in the shower and while driving and right before you fall asleep. And then somewhere around 20,000 to 40,000 words, something shifted. The excitement didn't vanish all at once. It just started leaking, slowly, like air from a tire with a nail in it. One morning you sit down and the file is open but you're not sure what the next scene is supposed to do. A week later you haven't opened it at all. A month later you start telling people about your "next" project.
The strange thing is, the problem almost never shows up at the beginning or the end. Beginnings have energy. Endings have gravity. The middle is where books go to die, and the reason isn't that writers lack discipline or talent or willpower. The reason is that something structurally and psychologically real happens around the 25,000-word mark, and most writers have never been told what it is. A few reasons this happens, and what to do about each one.
1. The book you're writing diverges from the book you planned, and you panic
You start a novel with an idea of what it is. Maybe you've outlined it. Maybe you have a loose sense of the arc. Maybe you just know the feeling you're after, the mood of the ending, the kind of book you'd want to read. And for the first 15,000 or 20,000 words, the writing cooperates. It goes roughly where you expected it to go. You feel like you know what you're doing.
Then, around 25,000 words, something happens that's hard to describe if you haven't experienced it. Your characters start making decisions you didn't plan. A scene you thought would take two pages takes eleven, and now the pacing is different. A subplot you hadn't considered starts asserting itself because it turns out one of your secondary characters has more to say than you realized. The outline, if you had one, stops fitting. The book on the screen and the book in your head are no longer the same book. Most first-time writers read this as a sign that something has gone wrong. That they've lost control. That the story is broken and they need to go back to the beginning and start over, or scrap the whole thing, or maybe they just aren't good enough to pull off a novel-length work.
But here's what experienced novelists know: that divergence is the book coming to life. It's a sign that the story has started to breathe on its own, that it's become complex enough to surprise you. John Irving has talked about this for decades. He writes the last sentence of his novels first. He knows where the book ends before he writes the opening paragraph. And when the middle of the book starts pulling away from that ending, which it always does, he doesn't panic. He rewrites the ending. He expects the story to outgrow his original plan. The plan was just a way in, a door. You don't live in the door.
The practical fix is deceptively simple. When your book diverges from your outline, update the outline. Don't update the book. Sit down for one session, not to write new pages but to re-outline from where you actually are, not where you thought you'd be. Look at what the book is becoming instead of mourning what you thought it would be. I'm not entirely sure why this is so hard to do in practice, maybe because rewriting an outline feels like admitting failure when it's actually just paying attention, but the writers who finish books are the ones who learn to follow the story rather than drag it.