I prefer concise and accurate documentation than clean code tbh. The reason is that if the documentation stated that it should perform something with side effects a,b,c then I at least know what to expect. When contributing, this also makes it easier to implement something because we have the requirement at hand. Understanding shitty code is easier than understanding human requirements. Shitty code is the language we use to talk with a computer, so at least you'll know exactly what will happen.