Outlines are great, but rarely is anything I write composed from beginning to middle to end. It’s better to skip to the end and write backwards to the beginning, jumping past the middle in my haste to begin the story I already know the ending of.
If it can be said that the past is a future that’s already happened, you can see the value in writing back-to-front, or middle-to-end.
The true subject of novels is time, said Nabokov, or he said something like it. The composition of time spaces, even if they are read from the top of the page to the bottom of the page, don’t proceed round and round in steady progression like numbers on a watch face. Why would they? We remember out of order, so why would anyone write it down in order?