This principle is necessary in the exercise of command. Before you can expect your Marines to perform, they must know first what is expected of them. You must communicate your instructions in a clear, concise manner. Talk at a level that your Marines are sure to understand, but not at a level so low that would insult their intelligence. Before your Marines start a task, allow them a chance to ask questions or seek advice.
Supervision is essential.
Without supervision you cannot know if the assigned task is being properly accomplished. Over supervision is viewed by subordinates as harassment and effectively stops their initiative. Allow subordinates to use their own techniques, and then periodically check their progress. The most important part of this principle is the accomplishment of the mission. All the leadership, supervision, and guidance in the world are wasted if the end result is not the successful accomplishment of the mission.