With radio and TV, it costs the same to produce and broadcast a show from a radio or TV station regardless of how many people actually listen to or watch it [1].
With a web site, the more people that visit it, the more it costs for hosting and bandwidth.
Websites having a higher marginal cost for each new audience member compared to TV and radio might have an affect on how effective ads have to be to pay for the content. I could see web ads needing to be more effective than radio or TV ads because of that marginal cost.
[1] well, sort of. If a show is popular, actors on the show might be able to negotiate higher pay, for example.
With a web site, the more people that visit it, the more it costs for hosting and bandwidth.
Websites having a higher marginal cost for each new audience member compared to TV and radio might have an affect on how effective ads have to be to pay for the content. I could see web ads needing to be more effective than radio or TV ads because of that marginal cost.
[1] well, sort of. If a show is popular, actors on the show might be able to negotiate higher pay, for example.