Sometimes when we write an essay we forget that we're speaking to someone (a reader). We also forget that the beginning of our essay is technically the first impression that we make on the reader, while the conclusion is our last chance to get the reader's attention. Rather than focusing on writing an essay that is simply "correct" (in terms of grammar, following your assignment requirements, etc.) good writers also consider whether or not they've left a lasting impression on their reader. Think about it: the movies you've seen and the books you've read, the ones that really stand out in your mind, probably had an intriguing opening and a compelling ending. Your essay topic may not be as exciting as your favorite movie, but that doesn't mean you can't make sure that your ideas stand out in the reader's mind.