Venn Diagram: Meaning of a Story/Poem

I struggled with English classes in high school.  I also struggled with writing classes (which you probably guessed if you read my last few blog posts).  But I could never understand why the teacher would ask me what the author was trying to say.  How was I supposed to know those random poets and obscure short story authors were trying to say?  I always felt that those teachers were just making stuff up.