They have a limited scope of action and limited deliverables.
Successful or not I was trying to call out the shortcomings of the role rather than the people working in it.
Every day I talk to project managers who probably do an excellent job meeting their deliverables and will be rated very well for doing so. Unfortunately what they do isn't the right thing but what they were asked to do. There's no reward for doing the right thing even if it's value-add. That same point is what I was trying to illustrate with my comment; the output seen here is the perfect manifestation of that kind of attitude.