It's not about not finishing as much as it is about letting something in unfinished state.
You can finish what you are doing right now, and start something else to get a clear view of the next step. Or take something you want to fix, and put a breakpoint it it and plenty of print, to make it sure nothing works and the day after you know where to start.
If you learn how to build a castel with a very specific era look and feel as an architect, would you not then be likely hired to build a similar castel elsewhere?
I Do this for a living, ave for 20 years. I've designed many "castles" with similar looks and feels, similar materials, they work similarly.
But I've never built the exact same castle, with the exact same Floorplan, with the exact same plans. That's what I'm highlighting that I've seen several times.
A cool aside, I love this song by Watsky called "cardboard castles". Having done this for 20 years (build "cardboard castles") I identify with it.