Think of when you are working on a large project and you all of a sudden need to refactor some module which then has a huge impact all over the application. This is similar to a novel where late into the book the author figures out they want to change some part of a main character (like their origin, name, just some kind of detail), which will require fixing it all over the book. Writers refactor similarly to programmers.

Writers have outlines. Programmers have design documents.

There are more parallels between the two, but I forget many of them right now.