The Vampire Diaries put a signature twist on the usual young-adult, coming-of-age storylines. Elena Gilbert and her friends' growing pains included controlling their bloodthirsty impulses, figuring out how to channel powerful magic, dealing with a werewolf curse, and trying to remain human and alive in a town overrun with supernatural creatures. The driving force behind the series' popularity was the love triangle between Elena (Nina Dobrev), Stefan Salvatore (Paul Wesley), and his older brother, Damon (Ian Somerhalder), which ended with Elena choosing Damon. When Dobrev exited The Vampire Diaries after season 6, the show faced several obstacles: declining ratings, creative fatigue, and expiring contracts - all of which ultimately led to the series ending with season 8.
Plec told THR that going into season 8, the future of The Vampire Diaries was still undecided. However, once it was clear the story would center around The Vampire Diaries' underworld, Plec felt the show was reaching its inevitable conclusion. And so, The Vampire Diaries concluded naturally without being canceled, though the announcement itself was a bit of a surprise.
"Once we started talking about quote-unquote 'hell' and quote-unquote 'peace,' which is the Vampire Diaries version of heaven, it felt like if we're telling those stories, and we're telling stories about our characters trying to find their ultimate redemption and salvation with the end result being peace or hell, then it certainly now feels like this is the last season. Because if you can't take those journeys all the way to their conclusion, then why are we telling these stories in the first place?"
Dobrev's exit forced the show to focus on the strained relationship between Damon and Stefan, and The Vampire Dairies began its descent down a darker path. The Salvatore brothers rehashed old grudges while battling villains felt like lesser versions of what the audience had seen before; they lacked the complex backstories and charisma of Klaus Mikaelson, Katherine Pierce, and Kai Parker. The romantic pairings were spent, and the show's creators ignored the fans' desire to explore the onscreen chemistry between Damon and Bonnie Bennett or Caroline Forbes and Klaus Mikaelson; there was no longer a compelling love story for the audience to root for. Even a three-year time jump failed to breathe new life into the show, as the season 7 finale's viewership was 1.04 million compared to season 6's 1.44 million.
Plec acknowledged the logistical and creative obstacles facing the series going into season 8 in a guest column she penned for The Vampire Diaries didn't end as Williamson and Plec had originally planned, and there are many "what ifs" surrounding Dobrev's departure as well as how it affected the show's quality and popularity in the aftermath. With the series' canon becoming increasingly convoluted, The Vampire Diaries ran out of steam. Thanks to Legacies, though, Elena, Damon, Bonnie, Caroline, and Matt Donovan live on even if they don't appear onscreen.