It's your responsibility to follow up in the sense that if you need them and they don't need you, then it's on you. But if you're reaching out to them about on

It's your responsibility to follow up in the sense that if you need them and they don't need you, then it's on you. But if you're reaching out to them about one of their responsibilities in the organization, then it's on them. "He dropped the ball" is a perfect reason for my not having accomplished a goal. Nagging might help, but it does not address the problem. On the other hand, "avoid regression to the weakest" is something to avoid. Not sure how to avoid that without "managing" people.