Dexter was one of the most popular and beloved dramas of the 2000s — until its final season, which ended with an extremely controversial finale. Michael C. Hall played Dexter Morgan on the Showtime series, a blood splatter analyst for Miami P.D's Homicide department who also spent his nights as a serial killer murdering "bad people." The majority of the show's conflicts revolve around Dexter's attempts to pass as an upstanding family man despite his murderous cravings, and keeping his bloodlust a secret from his girlfriend (and future wife), Rita, and his sister, Deb, a police officer.
In the finale, Deb suffers a stroke after successful surgery from a gunshot wound and is left braindead. As a hurricane approaches Miami, the hospital is chaotically evacuating. Dexter goes into Deb's room and unplugs her from life support. He then drives his boat out to sea toward the hurricane and drops her body in the water. He fakes his death in the storm and becomes a lumberjack in Oregon, abandoning his son, Harrison. This ending does not make much sense given Dexter's well-known pragmatic and logical thought process.
The Dexter finale feels forced and wrong because that's exactly what it is. The showrunner for seasons 1-4, Clyde Phillips, planned for the series to end with Dexter's death. While perhaps more predictable than the actual finale, this outcome would make a lot more sense given the death toll that Dexter has racked up and the enemies he's created along the way. After the airing of the finale, producer John Goldwyn revealed that Showtime would not let the writers kill Dexter at the end of season 8. Showtime's reasoning was that they were considering the show's core fanbase, who have a "relationship" with Dexter and would be furious about his death.
In an interview shortly after the finale, Hall cited the high amount of writing and production staff turnover throughout the course of the show as a reason why Dexter lacked "a cohesive narrative." These changes made Dexter's character attributes less clear and weakened the show's later seasons. In the same interview, Hall was dismissive about the likelihood of himself playing Dexter again. He stated that he has doubts about a new Dexter story being written compellingly enough to bring him back on board, but he also doesn't completely rule it out for the future.
The lack of a consistent writers' room is a legitimate reason for the show's disappointing ending. Other big shows like Lost and The Walking Dead have notably suffered from this as well. The finale may go down as one of the most hated endings to a show of all time, but that doesn't mean the series hasn't produced several acclaimed seasons that will help Dexter remain well worth watching.