Guidance Cards - Refactor
Part of Red-Green-Go!
Refactor Card 1
A good coder writes code that looks like it was easy and straightforward to do. Many of the examples by Brian Kernighan in his books follow this pattern. Part of the "trick" is coming up with a proper conceptualization of the problem and its solution. When we don't understand a problem well enough, we're more likely to over-complicate our solutions, and we will fail to see unifying ideas.
With a proper conceptualization of the problem, you get everything else: readability, maintainability, efficiency, and correctness. Because the solution seems so straightforward, there will likely be fewer comments, because extra explanation is unnecessary. A good coder can also see the long term vision of the product, and form their conceptualizations accordingly.