Writing maintainable code is a communication skill

It's the lack of clarity on how the code works, what it represents, and/or why it was written. Maintainable code is code that eloquently and considerately communicates to its reader how, what, and why it implements. You can write awful code as long as your function is well isolated, well tested, and well named. Maintainable code is not about communicating consistently or exhaustively. Some schools of thought consider all code comments to be failures of code expression. Trying to cram all business context into names of variables and functions is bound to make the code more confusing. It would be interesting to adopt a code quality standard along the lines of: "all new code must successfully convey how, what, and why, to at least 2 of your colleagues.