I have a problem that I test new UI frameworks on; generating celtic knotwork. I've written three of these now (React, VueJS, and Go manipulating SVGs). The first was hard because I had to learn how to solve the problem. The others were hard because I had to learn how that solution changed because of the framework.

There's a joy in rewriting software, it is obviously better the second time around. As the author says, the mistakes become apparent in hindsight and only by throwing it all away can we really see how to do it better.

I also sketch (badly) and the same is true there; sketching the same scene multiple times is the easiest way of improving and getting better.