Ultimately, a visualization is an attempt to communicate some pattern(s) in the data. Visualizations can suffer from the same issues as other forms of communic

Ultimately, a visualization is an attempt to communicate some pattern(s) in the data. Visualizations can suffer from the same issues as other forms of communication: - inadequate information. Readers can't draw conclusions from information you don't include. Commonly missing information: labels, scale, definitions, context for the data. - information overload. Readers can't figure out which specific conclusions you're trying to communicate if there are many possible conclusions. Highlight the things about the data that you want to bring out using words, colors, arrows, or visualizations of subsets of the data. - muddled presentation. A blurry graphic is as difficult to understand as writing filled with misspellings and poor grammar. A busy graphic is as difficult to understand as a long, babbling diatribe filled with unnecessarily complex vocabulary. An ambiguously labeled graphic is as difficult to understand as writing filled with ambiguous pronouns. - inability to dig deeper. Readers can't figure out if your conclusions are sound if they can't look at the details. Interactive visualizations (based on the complete data set) allow users to see how each bit of data fits into the overall picture, and to test your conclusions on subsets of the data. If all you present is a static graphic based on a restricted data set, it's harder to check if you've cherry-picked data. - unfamiliarity with the language or conventions. Someone unfamiliar with programming will have a hard time understanding certain HN posts, even if they're well written. Someone unfamiliar with bar graphs will have a hard time understanding a visualization based around them, even if it's a good visualization. - boring subject matter. You can make the greatest visualization in the world, but if the audience doesn't care enough to look at it long enough to understand, your point won't get communicated.