Management guru Peter Drucker said that as soon as you move one step up from the bottom, your effectiveness depends on your ability to reach others through the spoken and written word.
You must illustrate what they do not see, give reasons to actions, and build relationships.
You can only do that through communication. Remember, Hitler was an excellent communicator. Gandhi was an excellent communicator. Andres Bonifacio was an excellent communicator.
Leadership without communication is not only difficult, it is also impossible.