Having a hit TV series is one thing, but knowing when to end it is a whole other matter.
You can probably count on two hands the number of shows that actually found a perfect departure point from a dramatic perspective and actually took it, as there are many, many more that were either cancelled before their time was done, or worse still, limped on for a season (or ten) past their natural end.
And there are no more egregious examples than these 10 popular series, all of which gave fans an emotional, gratifying send-off...but misguidedly decided to keep going.
Driven by strong ratings and the easy potential to cash-in, these series were all milked past their organic conclusions, with results ranging from acceptable, to disappointing, to straight-up terrible.
For many fans, these are the real finales in their head-canon, and nobody's going to be able to tell them otherwise. If you haven't started these shows yet, just stop watching once you reach these episodes...