Penny was become “sadly one-dimensional” by the Big Bang Theory. Chuck Lorre Acknowledges in Early Episodes
On the first episode of The Official Big Bang Theory Podcast (via Deadline), Lorre explains that The Big Bang Theory‘s early episodes did Penny a disservice by focusing on her being a “goofy blonde who says foolish things.” He breaks down how it took him and the show’s creative team too long to realize that the best part of Penny is her intelligence and humanity which the other characters didn’t have. Lorre regrets Penny being “sadly one-dimensional” in the beginning but is happy that this was rectified as the series progressed.
Despite The Big Bang Theory‘s immense success, the sitcom was not without its shortcomings, especially in the early episodes. Fortunately, Lorre and his creative team stopped limiting Penny’s potential by forcing her into the archetype of the “dumb blonde” character. Many of The Big Bang Theory‘s best episodes, and the series as a whole, began to focus more on Penny acting as a foil to Sheldon Cooper (Jim Parsons) and his friends and using her social intelligence to help them navigate daily challenges and see the world from a new perspective.
Penny did not just exist to support the development of Sheldon and his friends, though. She becomes just as developed, if not more so, than the other main characters, and there is an exploration of her motivations and struggles. In terms of the sitcom’s best relationship, it is not a romantic one, but rather the unlikely friendship that forms between Penny and Sheldon. This relationship provides comedic and heartfelt opportunities for the show to demonstrate the invaluable nature of Penny’s intelligence and humanity, along with the positive impact she has on others.