At one "Open Mic" club which I used to go to regularly, there was a particular singer/guitarist who was so bad that he was hilarious. When he had a pickup inserted in his guitar, he asked the club organiser to make him up a lead for it - and the next week was presented with one with a 1/4 inch jack on one end and a mains plug on the other - the audience found it hysterical. Incidently, the organiser said afterwards that he hadn't actually connected the mains plug - just in case! However, after this incident he had singing and guitar lessons - and improved. I can remember someone saying later that "He'd gone from being hilarious to merely mediocre".