More often than not, sequels to critically and commercially successful films are losing propositions, as they tend to be compared to the originals and panned when they fail to live up to their predecessors. So it's only fitting that once a popular movie is made into a multi-part franchise (of three or more films), expectations are even harder to meet.
The following 10 film franchises can all be defined by the wild success of their original entries and the utter disappointment of the instalments that came afterwards. For each entry, the original film can easily be considered one of the very best movies of its kind - something that is fully capable of standing on its own as being iconic and genre-defining. And then, the powers that be in Hollywood came along and pumped out a bunch of sequels in order to create a franchise and milk every last cent out of a well-received character or concept.
Think about the entries on this list the next time a friend comes along and proposes: "Let's watch all of the movies in the XYZ franchise!"
If they mention one of the franchises written about here, tell said person your time would be better spent watching the original in the series and quitting while you're ahead. If they refuse? You might want to consider getting a new friend...