Businesses, organizations, client relationships, and personal relationships would operate exponentially better if every person made managing expectations a conscious priority. It is essential in every job position and in every relationship. Communicating what you will be doing and when you will be doing it immediately instills confidence. Communicating quickly when things change always lessens the discomfort (no guarantees it still won't be unpleasant). 

The concept is simple but it needs to be practiced.