Which means that if the muse grandly tosses about a number of ideas about a setting and character and plot, it doesn't matter how dramatic several of them are.
Only one can be the climax. Others have to be demoted to plot points.
The fun part of it is that while you want the most dramatic one to be the climax, there is the little matter that in isolation, it can be very hard to judge which one is the most dramatic. All the fun and glamor of trying to juggle a bunch of shiny, sparkling ideas that are like gems sitting in the jeweler's work tray, waiting to be slotted into the right location on the necklace. . . .
Fortunately, sometimes cause-and-effect, once developed, determines which one comes first and which one second. Then you have only to develop things so the second one is more dramatic.
And sometimes you can just pick. Arbitrary decisions can then sprout leaves and vines and roots and grow into place so thoroughly you can forget where it was you made the decision.
Still not fun before then.