Although The Big Bang Theory enjoyed success for 12 seasons, the show had some questionable storylines and scenes that even the creators and cast members regretted. Steve Molaro lost sleep over Raj and Penny sleeping together in season 4's cliffhanger, which he later reversed. Kaley Cuoco despised The Serial Apeist storyline and wanted it removed from the show, but Chuck Lorre insisted on keeping it. Simon Helberg grew tired of Howard's sleazy ways, and Kunal Nayyar was frustrated with Raj's quietness around women. Lastly, one scene got banned from the pilot episode, where Sheldon and Leonard visit a sperm bank, as it was out of character. The show truly began with Penny's awkward hellos to Sheldon and Leonard.