re: How long should a TV Show Run

It depends. I think having a definite endpoint really picked up the quality in Lost, and that went 6 seasons. The Wire is damn near perfect at 5 seasons. Parks and Rec, which is probably my favorite show, is out of narrative steam and its season 4 or 5 I think.

but I think a show like Cheers could have gone on indefinitely. And while people rip on The Simpsons for not ending, has the quality really dipped in the past 10 seasons? I admit it reached its zenith already, but once it plateaued after, say, Season 8, its been on a pretty solid level of consistent quality. Does SNL need to be cancelled? I don't think it does.

But I do think dramas really need to wrap it up in 6 seasons. I think your best season will usually be S3, but I'll give you wide latitude to take your bows in a sixth season, even if the quality dips.