I regularly read or hear people express preferences for certain chart types, as in, “Scatter plots are the most useful chart type”, “I love bullet graphs”, or “Clustered bar charts are better than stacked bar charts.”
The various chart types are just a set of tools, though, and, as with any other set of tools, preconceived preferences or inclinations to use one tool over another don’t really make sense. Does it make sense to be inclined to use saws instead of chisels? Or to prefer hammers over mallets? No, obviously, each tool is simply suited to different types of tasks and it makes sense to use the most appropriate tool for whatever task is currently at hand.
I suspect that one reason why so many people have “favorite” chart types is that choosing the best chart type for a given situation can be a lot trickier than choosing between a saw and a chisel, and preconceived preferences simplify that complex decision-making. Should I use a scatter plot in this situation? Or a merged bar chart? Maybe some lines to show covariation? Scatter plots are the most useful chart type. Decision made.
Obviously, this is not a great way to select a chart type, though.
While a novice might always reach for the same set of “preferred” chart types, a more experienced chart creator will choose the best chart type for the current situation from among a broad variety of types, without any preconceived preferences for specific types. They’re able do this because they’re familiar with the specific capabilities and limitations of many chart types, and they’ve developed the skills to quickly select the one that’s going to be most useful for a given target audience and situation, based on a variety of considerations. Simple heuristics such as “clustered bars are better than stacked bars” would decrease the quality of their chart type choices.
The catch, of course, is that it takes time and training to learn about the specific capabilities and limitations of a wide variety of chart types, and how to choose the best one for a given situation. For example, this is the decision-making process that I teach in my Practical Charts course just for determining if a pie chart is the best choice in a given situation:
(Click image to enlarge)
…and this diagram shows only a few of the 50+ chart types that we discuss in the rest of the course.
Now, I should mention that, while I don’t have favorite chart types, there are chart types that I don’t like. For example, I think that funnel charts, packed bubble charts, radar graphs and several other chart types are virtually never the most useful choice. They’re the “as seen on TV” tools that look great in the infomercial, but then turn out to be a lot less useful than they initially appeared when we try to use them for real work.
Outside of “as seen on TV” chart types, though, every other chart type is the most useful choice for a certain set of circumstances. To become good at creating useful charts, then, we need to learn about as many of them as possible, and to let go of our “favorites”.
By the way, if you’re interested in attending my Practical Charts or Practical Dashboards course, here’s a list of my upcoming open-registration workshops.