"I auditioned just for fun"

Clay Aiken's quote "I auditioned simply for fun" implies that he auditioned for something without any expectation of success. He was most likely not anticipating to be chosen for whatever he auditioned for, and was merely doing it for the experience. This might mean that he was trying something new, or that he was taking a danger and trying something he was not exactly sure he would be proficient at. It might also imply that he was merely trying to find a method to pass the time and have some fun. Whatever the case, Clay Aiken's quote suggests that he was not taking the audition too seriously, and was simply doing it for the enjoyment of it.