If a college instructor told you just to write a paper, what would you do? No other directions—just “Write a paper.” How would you proceed? Would you just sit down and begin writing whatever came to mind, such as the latest prospects for the local football team or how much you dislike the classic band Steely Dan? Even if you did start writing, how would you know you were going to get a good grade on the paper?
Because you have no idea what the expectations of the assignment are or who the writing is for—you do not know the audience or purpose of the writing assignment.