True Time
Drawing the gap instead of asking the brain to compute it.
A number that matters a lot to a firm leader isn't hours captured or hours submitted, it's the write-down that occurs as a result of the difference between the two numbers. Real work that quietly never makes it onto a bill. When that difference is the crux of the story, the visual encoding we choose ought to make it obvious how big or small these differences are, so that days with long red lines clearly indicate work that has gone unbilled.
- Why a double lollipop, not two bars?
- Side-by-side bars force the eye to estimate a difference from the negative space between their tops. It's a subtraction the brain has to compute, slowly and imprecisely. The double lollipop encodes that difference directly as one red segment, so the quantity you actually care about is drawn on the page rather than inferred.