Something I meant to say, but didn’t, is that one of the problems with folks’ prior expectations or assumptions about data visualisations is that they reveal a single truth. I’m not sure that’s the case (I’ve started pondering the phrase “no truth, many truths” in this respect) which is another reason I see the role of visualisation as being a participant in a conversation where you explore questions and ideas and try to actively tease out different perspectives around a hypothesis based on the data.

For a related take on this idea of “many possible truths”, see Paul Bradshaw’s The Straw Man of Data Journalism’s “Scientific” Claim.