“ Since individual competence is valued, each person strives to create their work product on time with high quality. Happily if we’re unable to do that, it’s easy to blame others upstream for deficiencies in the work products they constructed and you leveraged. And, for the person who created the “project plan” work product, to prove that was high quality, they’ll need your work to go exactly as they predicted. In fact, their value in the traditional software development culture is based on it. You not finishing your task on time affects their perceived competence.”
This goes for the agency world too. Producers are put in some of the toughest positions I have seen.