The Big Bang Theory has always been a source of controversy. When it first started, it was a relatively subtle show focusing on a group of "nerds" and their exploits. Within a few seasons, it was one of the most-watched shows in the world, paying its cast salaries that surpassed a variety of records. Audiences were split between loving its brand of humour and hating it, enjoying its playful nerd stereotyping and being offended by it.

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Despite these reasons and its slow decline in comedic value, its final season was recently watched by millions. We’ve compared the reasons that season one always remained the show’s strong point, to the reasons season twelve was actually the best.

Season One: The Humour Was Fresh

Back when The Big Bang Theory first hit our TV screens, we had never met a single character before. Chuck Lorre was well-known to many for bringing his trademark style to the likes of Two And A Half Men, but this was a very different take on the world to his past work, and thus, a window into a new facet of his mind. We’d seen things like The IT Crowd, but The Big Bang Theory provided a new look at "nerd culture."

Season Twelve: Amy and Bernadette

However, during season one, we never met Amy or Bernadette, Penny’s would-be best friends. In fact, Penny didn’t really have much of a life outside of Leonard and Sheldon’s apartment and the Cheesecake Factory. By season twelve, we knew everything about Amy’s awkward nature and Bernadette’s squeaky anger.

Season One: The Catchphrases Weren’t Overdone

One of the major problems with The Big Bang Theory didn’t emerge until the show was well into its final years: the catchphrases got old. At first, Sheldon’s surprisingly playful Bazinga was adorned onto red shirts around the world.

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By season twelve, it was now only funny when presented as a flashback to his once awkward persona, as the catchphrase itself lost all of its impact.

Season Twelve: Stuart Was A Main Character

Stuart and Howard talking in the kitchen over dinner on TBBT

We met Stuart rather early on in The Big Bang Theory as the owner of the comic book store that Howard, Raj, Leonard and Sheldon frequented. His loneliness was a major part of his character for a long time, so his eventual absorption into the main group was rather satisfying. In season twelve, he appeared in most episodes and delivered his deadpan humour way more often than he did in season one.

Season One: Howard Was Hilarious

Howard might have been quite a problematic character early on—his over-sexualisation and objectification of women were frequently criticised—but it’s impossible to deny that he was anything but the show’s comedic gem in its early days. When he met Bernadette, however, he became a whole lot more likeable and well-rounded, but, by the time we got to season twelve, he just wasn’t as funny.

Season Twelve: There Were Many Celebrity Guests

Wil Wheaton The Big Bang Theory

With The Big Bang Theory’s immense fame and success came a sizable budget. A budget so sizable, in fact, that it could attract a number of very famous celebrity guests. Over the course of the show, we were introduced to fictionalised versions of the likes of Stephen Hawking, Mark Hamill, and the ever-present Will Wheaton. Season one ran low on celebrity guests as the show found its feet, but season twelve was chock-full.

Season One: Raj Couldn’t Speak To Women

As many comedy shows do, The Big Bang Theory, unfortunately, relied on the fact that Raj was Indian to attain many of his character’s punchlines. This became especially prominent as the show wore on.

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In the earlier seasons, however, he had a genuinely unique personality quirk that allowed him to be more than the token minority: he couldn’t speak to women. This made for both interesting storylines and fantastic moments of levity.

Season Twelve: We Knew Everyone

The Big Bang Theory cast eating together

The Big Bang Theory was a little bit like The Office in its presentation of characters. At first, it relied on humour and personality quirks to keep people interested, but, by the end, we were there for the characters we now loved, pretty much no matter what they were saying. Many feel that the show went downhill in quality by the end, but we still loved the characters.

Season One: Sheldon Understood Nothing

Sheldon raising his eyebrows in surprise in The Big Bang Theory

Zipping all the way back to the other end of the show, however, we get the now world-famous humour of Sheldon Cooper. The fact that Sheldon had developed so much over the course of the show meant that season twelve had to rely on humor of different types and call-backs to how he used to act. His season one personality was definitely when the character was at its funniest.

Season Twelve: The Ending Was Incredibly Emotional

The Big Bang Theory Finale Group Shot as they look sad

The conclusion to the final episode of The Big Bang Theory was a truly emotional showing of the development each character had undergone over the years. Sheldon and Amy finally won their Nobel Prize, and all of their best friends were there to see it before Sheldon proved that he had finally turned into a loving, selfless, and caring man.

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