[melech_ric]

I'm old enough to remember a time before every TV station had a logo/watermark at the bottom right. In my mind, the logos coincided with the early 80s when VCRs became more commonplace. I suppose stations that licensed shows/movies, didn't enjoy the fact that people could record that content and reuse it. So... logos.

[dredmorbius]

Not that I watch much TV, but persistent logos ... and animated promos for upcoming features during the current programme, which still seems mind-blowingly bad ... were something I didn't notice until the mid-2000s.

I may well have missed thier introduction.