An important attribute of performance is that it is a complete art, unlike poetry, novel, drama, prose and other literary forms. After it is written or even published or performed, it is possible to modify or even re-create. Only when the performance is recognized and accepted by the audience can we judge the success or failure of the film. At this time, the production and creation of the film has been finalized, and it has solidified everything in the film through special production methods, which is almost impossible to modify. If you want to modify it, you must do it again. Go back to location, re-shoot, and re-print. Similarly, the effect in the process of re-correction can only be known through the screening after printing. In this sense, performing arts often coexist with regret. Therefore, people call performance: the art of regret.