Processes can't compensate for lack of competence
Having rules and processes is never a substitute for competence and understanding.
Following all the best practices in the world cannot prevent a team of mediocre programmers from creating a complicated mess that no one can understand.
Creating high quality products requires a lot of mental effort expended over an extended period of time. Good programmers have a lot of rules they follow that they themselves are not aware of, and they constantly adjust these rules as they gain more experience.
It is not possible to put all these mental heuristics into words, and it's not even desirable, for it prevents these heuristics from evolving.
Bad managers constantly seek new rules to enforce on the team, hoping to avoid past problems.