The effectiveness of counseling varies with goals, but it generally is determined by some kind of change taking place. As a counselor, you have a great responsibility to be ethical and non-manipulative in your interactions with your clients. There is power associated with your role that gives you great advantage over most clients. Use it wisely.
Counseling involves corrective behavior, and so does discipline.
Yet there is a great difference between the two. It is in your power as a manager to define the situation. Be sensitive to the different ramifications of these two, and give counseling a try first.