I’ve had that experience. I had to write code for a complicated reference counted datastructure. The code was a mess at first because I was approaching it the wrong way, but once I understood it well enough to write it correctly all the pieces fell into place. Extraneous complexity was eliminated, and all the possible mistakes turned out to be impossible. The resulting code is so simple and straight forward that anyone can read it and see that it is correct. And as is traditional, the first time it compiled it was correct in all respects.