A popular trope about writing mysteries is that the author starts with the ending in mind and writing the plot back to the beginning. It’s probably not used universally, at least not any more, but there’s a bit of a corollary to other art practices.
If you have an end in mind, or a grand vision of some kind, it’s easier to start moving toward it. The hard part is when your execution doesn’t match the image in your head.
I find if I start with that kind of overall vision, I can’t stay too wedded to the original concept. It’s easy to become disappointed and discouraged by my abilities, or to realize the original ending wasn’t really that great to begin with.
The thing I’m making may be better off going on another direction, entirely. It’s mostly about creating the map as you simultaneously make the territory.