The “petrol pump problem” emerged from a conversation with Jones a while back, and stems from a stupid error I found myself making at some gas stations.
The difference is small but significant. The first has large labels with smaller buttons above to select the petrol grade. The second example has large labels that are the buttons. The problem I was experiencing with the first example is not a positioning and/or manipulation problem familiar to common industrial ergonomics. By ergonomic measure the buttons are appropriately positioned on the pump. For the most part, they fit to me. The problem is that the label and button are separate. I want to them to be the same; I keep trying to press the label. The problem is one more familiar to software usability, and reminds me of the shift that has occurred on the web where the label is now usually the target. It’s less of now that you’ll see “for this, click here”. “this” is generally the link itself. Indirect to direct manipulation.
The proliferation of touch in to personal devices and public interfaces is pushing that model out to the physical world. Perhaps its a sign that I spend too much time on the internet, but this is a shift I feel I’ve internalized and suspect others are as well: There are no more buttons, we expect everything to be its own button.