As one of the main characters of Cheers, Diane Chambers' exit in season 5 was controversial; Shelley Long decided to leave the show despite its popularity. Playing the high-society waitress in the eponymous bar, Diane more often than not looked out of place in her workspace — that's what made her a great addition to the ensemble cast, being distinct from the typical patrons and employees at the pub.
To make Diane's stint in Cheers more interesting, she also developed a hot and cold dynamic with playboy bar owner Sam Malone (Ted Danson). While they obviously can't be more different than each other, it's clear from the get-go that they were mutually attracted to one another — something that the show played up brilliantly with their on-again, off-again relationship. Arguably, the pair perfected the will-they/won't they trope that is still popular in TV shows up to this day.
Things were going incredibly well with Cheers since it found its footing following a rocky first season. Viewership was high, and it's clear that the show was offering something special for the dynamic to enjoy the level of popularity it had. This is why the public was baffled when news broke out that Long decided to exit the series, leaving behind her Cheers character Diane — a career-defining role which gave the actress two Golden Globes and an Emmy. So, what made Long quit what appeared to be a great job?
Apparently, Long was looking to transition to become a movie star, and she thought that her widespread popularity in the TV landscape was enough to propel her onto the big screen. It's worth noting that at that point, this wasn't an exactly new practice: both Michael Douglas and Tom Hanks left their budding career in the small screen to try their hand with films — a massive gamble which obviously paid off. Immediately, it seemed to be a great career move for the actress. Fresh from her exit in Cheers, Long already had a hit in 1987 via Lesley Dixon's Outrageous Fortune, but it wasn't exactly a smooth ride from there as her movie career never really took off the way Douglas's and Hanks's did. Aside from her aspirations to be a movie star, Long's decision to leave Cheers was bolstered by having constant conflicts behind-the-scenes with her co-stars, particularly Danson and Kelsey Grammer, who played Frasier Crane. It's an open secret in Hollywood that, just like her character, Diane, the actress didn't really fit with Cheers' ensemble cast which famously got along quite well.
Instead of definitively writing Diane out of Cheers, the show found a way to allow her to exit with the idea that there's still a possibility that she could return. After abruptly being offered the opportunity to finish her novels in the season 5 finale titled "I Do, Adieu," she chose to pursue her dreams of becoming a published author and only postponing her supposed wedding to Sam. While she promised that she'd be back, both Sam and the viewers knew that she wouldn't. Until now, whether or not Long's decision to leave Cheers was worth it remains to be a favorite topic of conversation among TV connoisseurs and fans of the sitcom. As for the show itself, her departure didn't affect its popularity at all, with some arguing that its best years were after Diane left.