By Loren Mack on Sep 04, 2007
Loren Mack is a design architect in xDesign who creates strategic and tactical designs for the Service Oriented Architecture/Business Integration group at Sun.
Design isn't all about aesthetics, but aesthetics certainly make a difference. To me, design is part thought process, part style, and part usability; thinking about the problem you intend to solve, creating your solution with style and verve, and then making sure it works well for its intended task and audience. However, much too often in my everyday life I come across something that makes me growl — especially when that something encourages me to make a stupid mistake. Right about then the laugh-track goes off in my head, and I feel a bit like Jerry Lewis, only I'm not intending to do something goofy.
The Pull-Me, Pull-You Problem
I once locked myself in a skyway running between the second floors of two buildings in Des Moines, IA. Because of its cold winters, downtown Des Moines has connecting glass hallways that allow you to travel from building to building without actually leaving an enclosed space. It's great because it can be bloody cold outside that time of year. So how did I manage such a feat?
Well, the picture on the left shows a doorway similar to the one that confused me. And, while it was my error that caused the problem, it was the design that really encouraged it: door handles like these say "Pull-Me" to the person approaching the door. If you watch 100 people approach this door, I'll bet you 50 $imoleans they all try to pull the door toward them.
It turns out though, that the doorway had handles like these on both sides, so folks on either side of the door will likely end up pulling on the handle, which is exactly what I did.
The problem occurs when the door only opens one way. In this case, the "push" side (shown right) also has the "Pull-Me" handle, and in my case, so did the skyway. I pulled open the door at one end of the skyway, to enter, and then pulled (in vain) on the other side to get into the next building.
I then went back and pulled the handles on the door through I had just entered, and sure enough the door didn't open. I assumed that, since it was late in the day, the doors had locked between buildings. I was trapped like an ant in an ant-farm.
Eventually, someone else came through the door on the opposite side of the skyway, and I made my escape. Only then did it occur to me to try again and that's when I figured out the doors only opened into the buildings. I could've pulled on those handles all day and never gotten the doors open. Thank goodness it was a weekday, and I wasn't the only person working late.
The point of my story is the same as the story Don Norman used in 1988 to first describe what "affordances" are: the perceived and actual uses of a thing. In my example above, a C-shaped door handle around waist height indicated a grasp/pull action. This design is fine for two-way doors, but one-way doors could better indicate their functional direction by having a handle on one side, and a push-plate on the other. Norman suggests that "a good conceptual model allows us to predict the effects of our actions." So, in the absence of an affordance, at least put the word "Push" on the correct side for all skyway doors in Des Moines.