With all TV shows, one of the most important qualities is consistency. Viewers a far more likely to engage with a show that has a consistent quality throughout its run. In 2019, this was proven to viewers with the release of HBO's much anticipated final season of Game of Thrones, a stark contrast to previous fantastic seasons.

Related: 10 Best TV Shows Of All Time, According To Ranker

For many shows, the hardest season to crack tend to be the first and final season. The recent cancelation of Netflix's Cowboy Bebop adaption only goes to show just how hard it is to craft the first season of a show.

Parks and Recreation

The cast of Parks and Recreation season 1

Though considered by some to be one of the best pieces of comedy content released by NBC, some people forget the struggle that is the first season of Parks and Recreation's opening season attempted to set the tone for what would eventually become a much-loved series, season one of the show feels completely different from the rest of the series on rewatching.

Perhaps a result of needing time to find itself, Parks and Recreation was certainly saved by its shot at a second season. With many critics highlighting in retrospect that the opening season feels slower-paced and the characters don't feel like they do throughout the rest of the show, Park's and Recreation certainly struggled out of the blocks.

The Office (US)

Andy and Jim in The Office season 8

Perhaps one of the most surprising dips in quality for a TV show, departure of leading man Steve CarellThe Office faced the extremely difficult task of moving on without him.

Though there are still clear glimpses of the quality many fans have come to love, it is certainly clear that season 8 of The Office didn't best know how to plug the mighty gap left by Steve Carell's departure. Star of the show Jenna Fischer has even stated that "it always disappointed me that we didn’t trust in our core office group enough to continue the show without bringing in what I think we thought we needed.”

Lost

Kate outside looking dirty on Lost

Known by many for its disappointing ending, the creators of Lost were always going to struggle to wrap up one of TV's biggest cultural phenomenons. Though they tried, for some people, Lost season 6 left them with arguably more questions than answers.

Related: Every Season of Lost, Ranked From Worst To Best

With a shift in the quality of character development in the final season in favor of pushing hastily to the conclusion, Lost lost sight of what made it great and exchanged it for an ending which left many people disappointed. With critic ratings falling to 68% for season 6 it is clear to see the drop in quality.

It's Always Sunny in Philadelphia

The four MCs from It's Always Sunny season 1

Though still full of fantastic content and the trademark humor fans have come to love, the first season of It's Always Sunny in Philadelphia is certainly the hardest to rewatch.

With the show's first season opening without fan-favorite Danny Devito, fans can certainly feel the lack of his presence in the opening season of the show. Though a solid setup for the future of the show, it is certainly clear there is a gap in the dynamic without him.

Scrubs

Three characters from Scrubs season 9 next to each other

Replacing the much-loved main cast of a show and trying to move forward is always going to be a struggle. Scrubs season 9 certainly proves this point as it introduces a host of new characters for the final season of the show.

With the distaste for this season compounded by its release after a season 8 finale that many fans felt wrapped up the show effectively, Scrubs season 9 was certainly up against the odds from the offset. For many, Scrubs season 9 feels like a spinoff show living under the umbrella of the original series. Even series lead Zach Braff has made jokes about the much disliked season 9 on Twitter.

That '70s Show

Cast of That 70s Show season 8

It is quite clear that replacing the main character on a TV series after a long run is an almost impossible task. That '70s Show manages to prove this theory with its eighth and final series.

With Topher Grace deciding to quit at the end of season 7 and Ashton Kutcher leaving the show early in season 8, it was essentially an impossible task to replace and resolve the dynamic lost between the main cast in this final series of the beloved sitcom. With an audience score of 26%, a steep drop from the previous season's 79% it is clear to see the fall in the quality of the show.

The Walking Dead

Maggie watches as Glenn is beaten to death in The Walking Dead

The Walking Dead though often accused of suffering from excessive filler has managed to hold a relatively consistent level of quality since it arrived on screens in 2010. This quality was however disrupted by the show's eighth season.

With a slow approach to moving forward the story of the show and the controversial death of one of the show's most important characters, season 8 of The Walking Dead certainly had fans worried about the long-term future of the show. Fortunately, the arrival of Angela Kang as showrunner steadied the ship moving forward. Despite this, ratings from the season 8 premiere to the season 9 premiere fell from 11.4m to  7.92m, clearly showing a loss of viewership.

Community

Troy and Abed sits with coffee mugs in Community.

Community is one of the rare examples of a comedy show that managed to succeed immediately upon release. With fantastic reviews across its opening seasons, Community finally hit a rock upon the airing of its fourth season.

Heavily attributed to the departure of series creator Dan Harmon, Community season 4 certainly lost what made it so special. With further drama involving Chevy Chase using offensive language behind the scenes of the show ultimately resulting in his departure, it is clear to see that this season of the show was the most turbulent and poor of the run.

Game of Thrones

Arya, Sansa, and Bran sitting in a tent in Game of Thrones

Without question one of the most high-profile drops in quality of a TV series belongs to Game of Thrones. Though it had seven seasons of fantastic quality to build upon going into its final season, Game of Thrones dropped the ball massively.

Related: Well Written Game Of Thrones Characters Ruined By The End

With attempts to wrap up too many storylines in such a short amount of time, Game of Thrones cleverly set up stories and characters that were essentially bulldozed by the rushed final season of the show. Fan reaction even led to numerous petitions being set up to remake the eighth season of the show, showing a clear distaste for the final offering of Game of Thrones.

House of Cards

Clare Unverwood at the Oval Office in House of Cards Season 6

Perhaps it is unfair to judge House of Cards on its final season given the context, however the showrunners decided to release the series nonetheless. House of Cards season 6 very clearly struggled to find a way to conclude the show going into this season.

Though the performance of Robin Wright is to be ired, going into the show's sixth season it was always going to be an impossible task to effectively wrap up this show. With Kevin Spacey rightly removed from the show due to allegations leveled against him, perhaps a lack of a true conclusion would have been more fitting for the show.

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