Published novels with atypical story structures (I’m thinking, for instance, of frame tales or stories told out of chronology or stories told by a first-person narrator who’s not the protagonist, amongst others) are often very good! That’s because the authors had to exhibit tremendous control in order to make their story work even without the traditional things that pull a reader through the book.
But I’ve noticed that when we’re dealing with unpublished books (particularly mine), there’s often a temptation to resort to these structures when your book isn’t working. It’s like, oh hey, I’m not sure what my protagonist would say or do here, so let’s put her behind the fog of war. We’ll have the story be told by her best friend! Or I’m not sure what happens at the beginning of this book, so let’s start at the end!
The bad thing is you don’t realize you’re doing this. You just think you’re finding an innovative solution to the problem. If someone was ever to be like, “You don’t understand your own story,” you’d say, “What? No! I understand everything.”
But it’s hard to lie to yourself when you’re actually writing a book. And if you’re having trouble writing, there’s often a reason why. The solution here isn’t to pull some fancy stuff: it’s to reimagine your book until you actually understand it.