There have always been rules, and then there have always been reasons to break those rules.  Every medium, every art form begins with a set of rules.  Rules do change with time and culture but they tend to only change when there are driving factors or motives that create and control these rules.  But then there are people or movements that push, bend and when necessary break those rules. Geddes, Adams and Leibovitz have all pushed their art to the point of making the new norm from the obscure or inane.