I’ve thought about Super Hero movies starting with change (origin stories), then shifting to steadfast, finally going back to change when the series ends.
I assume this works with television series as well. Change bookends the series. Steadfast carries the middle.
I’d say the reason is because the engine of conflict needs to have enough steam to carry the show for 100 episodes (whatever the magic number is, I forget).
It would be the same for carrying a 10 book series.
The opposite just doesn’t seem very interesting (SCS), but maybe it could reflect a fall from grace and redemption story?
And all change would be strange (CCC) unless the stories had states of affairs that were seriously different (an 8 year old character version, a 13 year old character version, and an 18 year old character version).
All steadfast would work (SSS), but it would miss an interesting opportunity story-wise.
Maybe?