Too many to list, but to sum up: The executives in top leadership positions.
By overstepping their roles, micromanaging projects, and overestimating their engineering and technical prowess, the executives often times make a difficult or challenging situation much, much worse. And perhaps worst of all, when a project starts to spiral out-of-control, leadership point fingers back at their own people blaming them when, in reality, the origins of many problems are poor expectations set during initial engagements, and long before engineers are even involved in the process.