What Makes a Data Visualization Memorable?

Interesting piece in CGW:   The title question alone gives me pause.  I want to make data useful and objective.  I also want a data visualization to be the knowledge infrastructure for dealing with data and its meaning.  It's exactly the reason I often do not like Infographics, which mean to attract attention to data, and make it more memorable.  Often obscuring the actual meaning.   Give me a objective starting point for working with data, and support for further understanding it.   Not attention and spin control.