The best codebase I've ever worked on was when I started software development officially, I had zero knowledge of the stack for real, the codebase was run by just 5 mid level engineers, but based on how well structured and understandable it was, i was able to pick up the stack without reading a tutorial or a documentation, i would later read up on it when i started doing complicating stuff tho, but it's important for engineers to write good code to the extent that another person reading it does not have to look up something just to understand why this does that, and how stuff works in the code