I like all the movies in this series. I know some dislike the 2nd one, but I think overall it's still pretty good. Can anyone else think of film series six deep with all being quality films?? The first six Bond films were good, but a lot of the stuff that follows is not.
But to answer your question, the most consistent franchise is obviously Harry Potter.
Which one isn't good?
-From Russia with Love
-You Only Live Twice (yea the Connery being made to look Japanese is cringeworthy, but it still has ninjas raiding a bad guy base in a volcano)
-On Her Majesty's Secret Service