For me, there is usually a lot of fretting involved in the first draft. Does the main plot and subplot mesh well together, but aren't too matchy-matchy? Does the subplot complicate the main plot unnecessarily take over? Is one of the secondary characters getting too much screen time and taking over? Is my heroine actively protagging or being lead to all the answers?
This is my wrestling stage where I'm trying to be certain everything makes sense. There are times when I find myself arguing with my muse within the manuscript. I'll switch over to all caps when the plot is starting to twist and veer away from my plan for the book. I'll ask myself if the change makes sense, how will this twist fit into the plot, working it all out--and sometimes not. There are times where I'll write forward with the story when I run into a snag, and other times I have to go back and work out the problem before the story can progress.
Altered to Death is my 10th mystery, and once again who I designated as the murderer isn't the murderer. (I've also written 5 romantic stories but don't have this problem with them.) Sometimes when I discover the real culprit, it's not too big of a switch and I'll see that clues were there all along so it's just tightening up a few places, a tweak here and there, and it's all good. But other times, it changes the mood of the story and the heart of the story.
When that happens, it can create a huge shift and I have to "Humpty Dumpty" the story...break it part and put it back together. Usually, I can put it together with a few places needing clarifying or connecting more solidly to the story. Other times, it fits together I didn't notice some weak spots that even though they are patched, can still break the story apart.
The next phase of the life of a book is for "all the king's horses and men" aka my fabulous editor Erin, to help me "put it together again". And unlike poor Humpty Dumpty, my book does get put back together stronger, better, and no longer still on a wall where it might fall and break.
Stay tuned for the next part of the saga of the life of a book: Developmental Editing.