Subverted: The author had notes set aside just in case Troper's Saga became a huge franchise, and while he vacates the position of Troper's Saga author, his successors follow these notes religiously.
Double Subverted: ...until said notes were all exhausted, leaving future installments completely off the rails.
Parodied: The publishers of Troper's Saga have a machine specifically built to pump out more installments of Troper's Saga.
Zig Zagged: The Troper's Saga series has been losing steam ever since Part IV and the author is getting sick of having to churn out more, but then another author decides to reboot the series into something fresh, which inspires the original author to write future installments that carry the original spirit of the series it had in the beginning.
Averted: Troper's Saga is a standalone series with no plans of a sequel.
Enforced: The publisher demanded that more installments of Troper's Saga be created in order to maintain their Cash Cow Franchise.
Lampshaded: "Troper's Saga XV? I had no idea this series was still around."
Invoked: "We've got to keep making more Troper's Saga! Think of the merchandising!"
Exploited: The author of Troper's Saga ensures he and his estate get a cut of all the merchandising, spinoffs, and anything else their publisher pushes for as long as the franchise keeps going.