The authors draw a distinction between Information Visualization (infovis) and Statistical Graphics. The goals of Infovis experts are to grab attention and tell a story. The goals of experts in Statistical Graphics are making it easy for the viewer to identify unexpected patterns. Actually, I would revise that a bit and state that the goal of experts in Statistical Graphics to produce an image that allows the viewer to make fast and accurate comparisons. All of these goals can conflict and you often need to find a compromise.

[Andrew Gelman and Antony Unwin][gel1]. Infovis and Statistical Graphics: Different Goals, Different Looks. Unpublished manuscript, 2012-01-20.