Readability matters
The computer might be able to understand your code, but what about your co-workers? Or you, a few months from now?
Put effort in making your code readable and understandable.
The first draft might pass the tests, but it is often cryptic and inelegant.
When a programmer starts building a functionality, she doesn’t know what classes, methods and variables she’ll end up with. She’s learning as she goes.
Eventually, the code will start working, but it will look like a brain dump. The code that “just works” is confusing and difficult to maintain.
Instead, spend some time refactoring the code. Imagine that you’re seeing the code for the first time - would you understand it?
Pay attention to naming. Make sure the intention is clear. Put comments where needed, or better yet, create readable, self-documenting code.
The tests are your safety net, so don’t be afraid of breaking stuff - be creative! Once you’re done, show the code to a coworker and ask for feedback. This way you’ll ensure that the code is high quality.