“Dexter” had its series finale Sunday night, giving the show its highest ratings and some of its most negative reviews. In its early seasons, the show was a hit with both critics and audiences, but as it dragged on through eight seasons, it became increasingly apparent that the show was struggling to find ways to keep viewers interested. Even though the ratings held steady, reception cooled considerably.

READ MORE: 'Dexter' Series Finale Review: 'One Last Kill'

This struggle is by no means unique. If a show can bring in viewers, networks will renew a show year after year regardless of quality.  Unfortunately, this often means that once creative and well-produced shows drag on long past their primes. The end of “Dexter” marks one fewer show begging for cancellation, but dozens remain. Here are just a few:

“Bones”
In what is perhaps the most frustrating example of a will-they/won’t-they relationship, “Bones” spent six years arbitrarily keeping its main characters apart and when they finally did get together after endless teasing, the new relationship added very little. “Bones” was a gritty, suspenseful show in its early seasons, unafraid to supply gruesome imagery and push its characters to their limits. As the years passed, that edge dulled and the show began to rest on its laurels.
Number of seasons: 9
Should have ended: Season 3

“Grey’s Anatomy”
“Grey’s Anatomy” certainly isn’t a show afraid to push the envelope. Rather, it’s a show that’s grown increasingly tiring over the seasons as it bends over backwards to top what’s come before. There’s been several car accidents, a ferry crash, an ambulance crash, and even a plane crash. A shooter has taken the hospital hostage. There was a bomb inside a person. A shocking percentage of the hospital staff has died. Not only has the show weathered tragedy after contrived tragedy, its survived numerous cast changes and there's plenty of behind-the-scenes drama, leading ABC executives to believe the show can continue forever. Perhaps they’ll change their minds in Season 15 when the cast is operating on the moon.
Number of seasons: 10
Should have ended: Any point before the musical episode

“Modern Family”
Fresh off its fourth consecutive Emmy win for Outstanding Comedy Series, “Modern Family” isn’t going anywhere. The show can credit its success to broad appeal—everyone’s family can be frustrating at times—but aiming to please a wide range of viewers has kept it from being good in some time. With the exception of the occasional funny moment, “Modern Family” makes poor use of its talented cast, relying on caricatures and formulaic stories that leave the show feeling timid and safe.
Number of seasons: 5
Should have ended: Season 2

“Glee”
One of “Glee’s” many, many problems is its confusion about the tone it’s trying to convey. Is it a high school satire? Is it an honest look at teenage problems? Is it an after school special? Is it an hour-long music video? The show has been all four, often within the same episode. Between a ham-fisted school shooting episode and a drawn-out “catfish-ing” sub-plot, “Glee” has doubled down on drama in recent seasons, making its lighter moments seem inappropriate and out of place. Season 5 begins with what promises to be a sunny tribute to The Beatles, followed by an episode dedicated to recently deceased cast member Cory Monteith, and “Glee” hasn’t inspired any confidence in its ability to handle the transition with any of the necessary grace.
Number of seasons: 5
Should have ended: When the musical numbers stopped being entertaining enough to carry the show

“Two and a Half Men”
When Charlie Sheen publicly criticized “Two and a Half Men” and was subsequently fired, it seemed that the juvenile sitcom was destined for an unhappy end. However, Sheen’s rampage seemed to renew interest in the show, allowing it to continue with Ashton Kutcher in his place. When Angus T. Jones followed his former co-star’s footsteps by calling the show “filth,” he also left the show and was replaced by Amber Tamblyn. With only 40% of the show’s original men remaining, TV viewers are primed to once again forget the show exists.
Number of seasons: 11 (!!!)
Should have ended: After Charlie Sheen’s rampage

“CSI: Crime Scene Investigation”
“CSI” is just one of a several crime procedurals that have dominated television for the past decade. They carry on for years without any semblance of character development or serialized storytelling. Between “CSI’s” many iterations and the different versions of “Law & Order” and “NCIS,” these highly episodic shows have had their day. Despite making for good background noise and mindless entertainment in syndication, procedurals like “CSI” are typically boring and predictable, but their decent viewership keeps them on the air.
Number of seasons: Including its spin-offs, 32
Should have ended: In 2005

“The X Factor”
Simon Cowell’s presence makes it difficult to not see “The X Factor” as a pseudo-spin-off of “American Idol,” one of the original singing competitions on TV. “Idol” used to be a huge hit, attracting millions of viewers and producing stars like Kelly Clarkson and Carrie Underwood, but by the time “The X Factor” debuted in the US, reality singing competitions were a dime-a-dozen and viewers were beginning to lose interest. “The Voice” manages to succeed with the added dynamic of the coaches, but “The X Factor” sticks to the same tired formula. “The X Factor” gets even lower ratings than the declining “Idol,” suggesting that viewers are no longer entertained by Simon snickering at bad auditions.
Number of seasons: 3
Should have ended: Before it was imported to the US

Reach Staff Reporter Reid Nakamura here.