Is it just me or is this photo totally confusing?
Here are five quick tips for creating a better interface, to accompany this fine example of what NOT to do when designing for ease of use:
1. Create clear visual hierarchy.
I have no idea where to start here. Do I pay first? Select my gas type? What are the steps in the process? Do I look to the left, or to the right? Help!
This could be done with layout, by placing the user interface elements in order top to bottom, or left to right, or with simple numbering. Either scenario could also be helped by a bit of instructional text.
2. Indicate choices and decision points.
All four of the yellow boxes say "Push to Start." Do I push all four of them? Or do I select one? The instructional text, while well-meaning, is unclear because it doesn't acknowledge the choice. And what am I choosing anyway? It's hard to tell from this pump.
3. Related items should be grouped together, visually, spatially, or both.
The arrows under the "Push to Start" boxes point down, towards the LCD screen. But each of the buttons (yes, those yellow boxes are the buttons) relates to the gas type and associated price above. This could be solved a number of ways: the arrows could be above the text, creating a line from the gas price to its corresponding button, or there could be instructional text placed between the prices and the buttons that reference the gas, the price, the choice, or pushing the selected button.
4. Similarly, input and output need to be in the same place.
The instructions and feedback for the touchpad, such as "Enter zip code" and "Would you like a receipt?" aren't even on the same piece of equipment as the touchpad itself. So when a person tries to use the touchpad they're likely to miss the feedback altogether. Even once it's discovered, the need to go back and forth from screen to touchpad when they're so far apart is frustrating. Input and output should be in the same place. Is that so hard?
5. Instructional diagrams should be instructional.
Show someone how to put the credit card in the slot properly, once. Or if there are options, at least use the same perspective. Don't use mirror images of the same illustration flipped; it requires too much work to understand whether they're the same drawing or two different ones. Maybe it's just me, but the angles throw me off. Diagrams should not confuse.
Jennifer Bove is a founder and principal at Kicker Studio in San Francisco and on the faculty of the School of Visual Art's Interaction Design MFA department in New York. She travels, a lot.