Code is a reflection of a programmer's skills and mindset. Good programmers always have an eye on the future - how the code will function when requirements or circumstances are not exactly what they are today. How scalabale it will be? How convenient it will be when I am not the one maintaining this code? How reusable the code will be, so that someone else doing similar stuff can reuse the code and not write it again. What when someone else is trying to understand the code that I have written.
When a programmer has that mindset, all the other stuff falls in place nicely.
Note: A code base is worked on by many programmers over time and typically there is not a specific designation of code base to a programmer. Hence good code is a reflection of all the company's standards and quality of their workforce.