I wonder when storyboarding started. It's certainly most associated with animation, though it's also used in movies and sometimes in stage plays.
But animation is so incredibly careful. Every stage is defined in such great detail. You can take a script and go film it; animation is handled by so many people that you just can't do that.
Thus, the storyboard. Each shot is drawn on one or more cards. Every major action is captured, like a butterfly, pinned up on a board, pointed at, and discussed. Characters are discussed in contrast to each other, action and camera angle are analyzed for impact and clarity.
Because several different artists all have to collaborate to make each shot. One draws the background, another draws the characters, while a third draws special effects. And the next or previous shots might be handled by completely different artists. So Hugh might animate Sylvester entering a room, while Rudolph animates him walking up to the counter. But it has to look seamless, like it's the same character performing one action as shot by two different cameras.
The odd thing about my storyboards is that I'm not starting from a script. I have a dozen action cards, which describe the major sequences of this short film in a few words. I take each of those, and draw storyboards for each one.
So, even though I can see a lot of the animation in my head, as I storyboard I often hit a moment that I hadn't envisioned. So I stop, and think about it, and do other things. Within a day, I have a solution, and I can continue. It's slow going, but it lets me solve problems visually, as they'll look on screen, instead of solving them in words in a script.
(I also have the luxury of being the only person drawing the shots, so I don't have to worry about people debating my choice of camera angle.)