You don't refactor enough
There are a million ways to implement something. This also means there are a million decisions to make too. Then it’s only natural that you didn’t make all the right decisions on your first try. Probably not even the second or third. Extreme Programming promotes a practice called Relentless Refactoring.
You need to refactor relentlessly to get anywhere close to a great implementation. Iteratively working on the same problem helps us to understand it better and better. Each attempt will reveal new parts about the problem that you did not consider before.
Review your own code, new insights will allow you to elevate your code to a higher level.
Refactoring is what you should be doing all day
Unless you are drowning in tech debt, I don’t think devs should ever surface refactoring to the level of planning. Refactoring is what you should be doing all day every day. As @BryanFinstersay, it’s about keeping your work area clean and tidy. It is an investment, not a cost.