A Failure to Communicate.

Bill Lindeke occasionally posts "Signs of the Times" he encounters while documenting city life. Here's one he found on a new bus, instructing riders how to open the doors. (I've added a little more help....)

It took me back to my days of teaching information design and Don Norman's The Psychology of Everyday Things, where he introduced the term "affordance" to describe physical features that "afford" a user control over a function — in this case, opening a door.

Now he says,

I should have used the term "perceived affordance," for in design, we care much more about what the user perceives than what is actually true. What the designer cares about is whether the user perceives that some action is possible (or in the case of perceived non-affordances, not possible).

Here's an example of another door, from an airport entrance. No matter how many times I go there, I am drawn to the panels on the sides of the opening because they are outlined in green with green rectangles that mimic push bars, while the center doors are in effect canceled out with red slashes that seem to signal stop and arrows warning that the doors open automatically.

So many of our doors are designed with perceived affordances that send confusing signals. Look at the bus doors. We are accustomed to pulling on protruding door handles and pushing on flat bars or panels, so whenever a door violates the convention, a sign is required. I suspect those "handles" serve as stair rails when the doors are pushed inward.

What may have seemed like a clever design is marked as a design failure by the words on the yellow tapes, and the handwritten arrows indicate the tapes are also insufficient to override what those handles are saying.

Norman again:

Words alone cannot solve the problem, for there still must be some way of knowing what action and where it is to be done. This requires a convention of highlighting, or outlining, or depiction of a actionable object. It is also well known that single word labels fail for most people -- everyone has a favorite word, but the variety of preferred words is overwhelming. Words also cause problems with international adoption. Thus, road signs often use graphics -- an international standard on road sign graphics exists. Alas, most people do not understand those standards. It is also the case that words are understood more quickly than graphics -- even a well known, understood graphic. Words plus graphics are even more readily understood.

This one, encountered near biffies on a mountain trail, I think I can grasp without the graphics.