10. She Wasn't The Original Lead Female In The Big Bang Theory
In spite of the fact that Kaley Cuoco's character Penny is now arguably the most popular character on the show, The Big Bang Theory actually kicked off without her. The unaired 2006 pilot episode of the show (which also included a creepily more sexually-wise Sheldon Cooper) actually introduced the intended female lead of the series Katie - a character in the mould of Penny, what with her being streetwise, hard-as-nails, but emotionally vulnerable, but with far more emphasis on the "streetwise". Katie was found on the curb, crying, after her boyfriend had kicked her out and left her homeless, and she was taken into Sheldon and Leonard's home (on Leonard's suggestion, but much to Sheldon's chagrin). Her abrasive and sarcastic nature meant that she was a lot less likeable than Penny and the bosses behind the show opted to drop her in favour of the more cheerful and bubbly Kaley Cuoco character.
