Why don't cable operators switch all programming to VOD like HBO has many of their shows On Demand?

Question

Why don't cable operators switch all programming to VOD like HBO has many of their shows On Demand?

Answer 1

It's a question of bandwidth.

If you have three thousand, say, customers all wanting to watch different programs, and they are on the same branch of cable, the cable would need 3000 channels of bandwidth.  Most cable systems can handle only about 200-500 max.

Plus the equipment at the head end (cable office) would have to be sophisticated enough to handle that many simultaneous feeds.  There are ways to mitigate these problems by downloading popular movies to your DVR while you aren't using it, and then when you "demand" the movie, it's on your DVR already and they don't need a cable channel to send you the feed.  But as you can imagine, this has drawbacks too... your DVR is being used to store movies and programs you don't want, taking up valuable space.