Once the page breaks are determined in the liquid phase, the text can't be changed. Once the page is printed in the solid phase, the poorly kerned headline can't be adjusted. I've used a print example but you could fill in any number of different analog media, be it film, TV, sound, whatever. In analog, the process of making the gaseous information usable is the process of making it into an immutable solid. Compare all this to digital information.
Digital information is much more malleable because it's made of bits.
Bits are liquid. Bits are flexible. Bits can be collected, copied, manipulated, and distributed innumerable times without loss of fidelity or quality. It's one set of bits, start to finish. Think about what the production process on a digital publication, say a web magazine, would be like.