The Principle of Priority states (a) you must know the difference between what is urgent and what is important, and (b) you must do what’s important first.
Steven PressfieldThe problem I've always discovered in my own work when this kind of thing happens when you hit the wall is there's almost always a reason. You've almost always made a mistake in the initial conception of the project. You misapprehended something or you thought something would work and now you're three quarters on the way through and you see that it doesn't work.
Steven Pressfield