Later happenings had no set rules, only vague guidelines that the performers follow based on surrounding props. Unlike other forms of art, Happenings that allow chance to enter are ever-changing. When chance determines the path the performance will follow, there is no room for failure. As Kaprow wrote in his essay, "'Happenings' in the New York Scene", "Visitors to a Happening are now and then not sure what has taken place, when it has ended, even when things have gone 'wrong'. For when something goes 'wrong', something far more 'right,' more revelatory, has many times emerged".