You should always brew what you want. Just as reading a recipe book doesn’t force you to brew only those recipes, reading the Style Guidelines doesn’t mean you have to change your brewing habits. The BJCP Style Guidelines do help people learn about the many types of beer in the world and what makes them unique. If you do not have any interest in learning about the world of beer or you never enter competitions, then the Style Guidelines may have little value for you.
Our goal is to provide structure and process for fair competitions. Style guidelines allow all brewers to compete on a level playing field. If you never enter competitions, then the guidelines may not have much value to you. If you do use them to get brewing ideas, that’s great.