I kinda thought that the purpose of communication was to impart something (knowledge, emotions, transcendence, etc.) from one consciousness to another.
How you do it (highly verbal/information density or highly visual/information density or highly olfactory/…) is dependent on two things: 1) what tools you have to communicate with, and 2) the intended audience–flashing graphics may have as little effect to a blind audience as shouting would to a deaf audience.
It’s interesting that nobody’s mentioned that background can impart as much information as foreground. Whitespace can help transform singular points of data into patterns that convey information with lower boundaries of perception and shorten the distance between sender and potential receiver(s).
I guess it’s as simple as remembering your message and your intended audience–regardless of the medium the message is being transmitted through. Of course that presumes that both you and your audience share enough commonality (an information-dense presentation in Etruscan is less likely to be understood than a simple line drawing).