Barriers to Quality at Wikipedia (and potentially other Wiki projects)

@Philippe: I accept the fact that there are guidelines in place already. However, all major Wikipedia projects have different guidelines and problems due to a different culture and way of working. Advising wp-en to appoint a commission to rewrite a certain guideline is a good practical idea, but can only work for that project. Wp-de has different problems. As we have only 2-4 recommendations to make, I would prefer to make them beneficial to all projects. On the other hand, we shouldn't be too general either. How to solve this paradox?