The carcasses of dead television shows line 2014 like roadkill. More than 70 shows were canceled during the year, according to websites that track such things. Some had enjoyed long runs and had simply reached the point of diminishing viewership that practically all series encounter eventually. Others lasted only a few episodes.

If nothing else, this collection of corpses proves that television viewers are a fickle lot. Sure, there are plenty of bad shows and lousy actors in 2014’s dustbin, but there are good ones, too. So what can we learn from the carnage? Here are some lessons from the 2014 Cancellation Calendar.

JANUARY

The lesson: Nostalgia about nostalgia has limits. It’s been 10 years since HBO’s “Sex and the City” ended, so fans now look back on it with wistful reverie. Perhaps CW was trying to capitalize on that with its 2013 series “The Carrie Diaries,” a prequel about the teenage years of Carrie Bradshaw (Sarah Jessica Parker’s character, played in “Diaries” by AnnaSophia Robb). Would original fans watch with their tween daughters? The series ended Jan. 31.

Image Simon Templeman on “The Neighbors” on ABC. Credit... Michael Ansell/ABC

FEBRUARY

The lesson: Two X’s is one X too many. In 2013, FX introduced a fearless, provocative series called “Legit” starring Jim Jefferies, the Australian comedian, and featuring a memorable performance by DJ Qualls as his friend Billy, who had muscular dystrophy. For the second season, which began Feb. 26, it was moved to the new and terribly named FXX, an offshoot channel. Apparently viewers didn’t follow, and the show died.