Is it ratings? Possibility of strong storytelling using similar ideas with new characters? Market saturation?
No, I think it is the amount of pop songs the network can use from the same band.
I was watching CSI: Miami last night and was actually paying attention to the opening credits. Well, as people probably know, CSI uses the Who’s Who Are You? and CSI: Miami uses the Who’s Won’t Get Fooled Again. So, by my calculations (and my only Who album, the latest greatest hits CD set) CBS can support about 8 more spinoffs for CSI.
Any other ideas?
(And yes, I am aware that market saturation, ratings, and the will to run a good idea into the ground probably account for much more. But I like my theory.)
The new “Star Trek” series seems to debunk your theory. Granted, all the ST themes tend to be bombastic and fairly bad, but they used to be bad in a grand, campy way. Now “Enterprise” has ditched the orchestral music in favor of a mind-bogglingly dreadful generic pop song. However, it is (from what i’ve seen of it) better than the last two ST spinoffs.
My theory is that networks will keep churning out spinoffs of successful series so long as the crappy retail tie-in products that result from the series keep selling. Again, look at “Star Trek” as an example. They keep making spinoff after spinoff so that they can justify cranking out more and more plastic action figurines and model starships and new versions of Star Trek uniforms, etc. That’s where the real money comes from.
“Batman” and “Superman” are other good examples. So long as t-shirts with the "S-logo"or “Bat-logo” keep selling, DC will crank out new tv shows and movies to justify making the merchandise.