Attendess of my Copenhagen seminar this week saw an example of a Type QV chart (description of Trifecta checkup here), where the biggest problem is a disconnect between the question being addressed and the visual form.
The visually arresting form makes the number 60 scream. It is a small puzzle to figure out what 60 stands for. The red color is the 9th worst level of corruption out of 10 given in the scale. There were 60 countries placed into this level.
It's all very meaningless. The chart itself is proof that the countries were divided into uneven - apparently arbitrarily sized - segments. We learn nothing about how this "corruption perceptions index" is constructed, and which or how many countries were rated in total.
And even if all those issues could be resolved, knowing the histogram of countries ranked by perceived corruption does not tell us anything about corruption in those countries - it only informs about a minor aspect of the ranking scheme.
Notice, also, the country labels provided on the left column include just 7 countries, those in the best and worst levels, thus missing all of the sixty countries that caught our attention.
The last baffling decision is to create an eleventh phantom level dressed in black.
To reconstruct this, one first has to decide on a worthwhile question to illustrate.