Apply the control model for managing ineffective performers

Why is it that first-level supervisors usually spend more time managing ineffective performance than do C-level executives?

How might an athletic coach apply the control model for managing ineffective performers to improve team performance?

Why should management be willing to rehabilitate employees through an employee assistance program when so many workers have been downsized in recent years?

Why might interacting with coworkers, bosses, and customers through social-networking sites result in a productivity drain?