If you lead a team, you want them to win. Only then will you achieve the goals of the entire organization. Unfortunately, most teams experience an expectation gap. They don't fully understand what is expected of them and their role. This causes frustration, anger, disappointment, and loss of trust.
In Matthew Kelly's book, The Culture Solution, he says the hardest expectations to manage are the ones we don't know about. Everyone on your team deserves to know where they stand and what is expected of them.