The Context of Data Visualization - Data Visualization: A Successful Design Process - page 18

Furthermore, for interactive and animated visualizations, remember Amanda Cox's
quote—"just because you can, doesn't mean you should." Don't succumb to the belief
(like I did for many years) of thinking a visualization is a platform solely to showcase
your technical competence.
Cluttering visualizations with fancy interactive features is a trap that is easy to
fall into and leads to projects that look nice or are impressive technically but
fail to serve their intended purpose. Instead, they interfere with the efficiency
and effectiveness of the information exchange thus demonstrating a failure to
synthesize form and function.
Creating accessibility through intuitive design
The following is a quote from Edward Tufte ( http://adage.com/article/
adagestat/edward-tufte-adagestat-q-a/230884/ ):
"Overload, clutter, and confusion are not attributes of information, they are
failures of design."
When you next happen to be in a town or city center, take a look around you and
observe how often people are confused by and struggle with the basic operation
of correctly opening and entering doors into a store. Notice how the accessibility
and function of a door—the simple act of opening and walking through it—is often
impaired through a lack of intuitive design.
The method of opening a door should be straightforward, but often the aesthetics of
features such as stylish door handles means we pull when we should push and we
push when we should pull. This is a flaw in the intuitiveness and logic of the design,
a failure in perceived affordance—it doesn't do what it looks like it should do.
This idea is an important concept to translate into visualization. As we have
already outlined, we are trying to exploit the inherent spatial reasoning and pattern
recognition functions of visual perception. We don't want people to have to spend
unnecessary time thinking about how to use or how to read and interpret something.
When you are creating a visualization, you are integrating visual design with a
subject matter's data. The former is the window into the latter, and it is the design
and execution of this window that creates the accessibility.
But it is important to create a distinction between accessibility and immediacy.
The speed with which you are able to read or interpret a visualization should be
determined by the complexity of the subject and the purpose of the project, not by
the ineffectiveness of design.