If I want a manual, I want it as text, or possibly html. That way, I can go straight to the part I want to look up, expecially if there's an index.
I don't want a video. I don't want to sit through an hour of tedious explanation of things I already knew. I don't want to fast-forward and try to find the information that I need.
Video does have a place, of course. When I was dismantling my bike motor, it was very good to have a video, because that told me whether the thread on the motor was left hand or right hand, a detail that the text didn't mention.
But the worst videos that I'm seeing now, are videos that are actually just a still picture, shown to you for 10 or 30 seconds. Why?