Natural forces will halt any progress eventually. In literature, it is up to the author to keep the story interesting, and thus counteract that which would bring it to a grinding halt. Just as in a romantic relationship, when the eyes start to wander, the desire is lost.
A good tale will seduce the reader, encouraging them to indulge in every word. As a work progresses, the excitement should build. Or at least the interest should deepen. Either way, the reader becomes engrossed in the proceedings.
There are many ways to build momentum in a story: flesh out the characters, expand their world, add a little mystery, or sharpen the terror. All of these things come down to increasing interest. Once the story becomes predictable, the reader will predictably seek out more bountiful fields.
The author has the advantage of holding all the cards. They know what is behind the locked door. A character’s hidden agenda is clearly seen to them. But the trick is in the sleight of hand, drawing the attention away from what you are really doing.
And thus, the tension builds; since the reader has no idea what will happen. As they continue along, more secrets are revealed. One must be attentive, or a significant detail will go unnoticed.