First, you write essays in order to gain marks so you can pass exams which allows you to graduate at the end of your university career. But in order to pass these exams you need to demonstrate that you understand the subject and can present a clear and logical argument. One of the reasons you come to university is to improve your chances of getting a good job. One of the main skills that you will learn at university is how to write a coherent 'report'. This applies not only to marketing or management courses, but also in the social sciences.
Most students have problems, particularly initially, with preparing and writing essays.
A good style, like most things in life, is something which involves work. Perhaps the most important advice you can be given is to think about your style and how it can be improved. It doesn't happen in that way. Your difficulties with an essay may start well before you begin to write, at the stage where you are reading books and articles and taking notes. You will need to devote enough time to this preparation despite the other distractions of University life.