Donald Norman’s book The Design of Everyday Things is an entertaining and enlightening guide to making products more usable. The book is full of anecdotes and case studies about things that ought to be easy to use, but aren’t. For example, Norman notably opens the book with a closer look at doors. He confesses that he sometimes pulls when he should push (or vice versa.) I’ve often done the same thing myself. So have you. Chances are, you probably felt stupid that you couldn’t open a door right on the first try. You may have even hoped that nobody saw you looking like an idiot. But, as Norman points out, the error isn’t yours: It’s a design flaw. A simple machine like a door shouldn’t allow for users to get it wrong. The design should influence our actions in such a way that we always operate the door correctly. It should not come down to trial and error.
From doors, Norman moves on to more complex examples of “everyday things,” but the principles of usability stay the same even as the engineering under the surface gets more complex. The consequences of misusing the products can also rise along with the complexity: When you pull a door you should push, the negative outcome is that you feel embarrassed. What happens when bad design causes somebody to misuses the control panel at a nuclear power plant?
I highly recommend The Design of Everyday Things based on its obvious merits. It sets out to explain user-centric product design, and it does so in text that is informative and accessible. It may require the specialized skills of an engineer to make a watch or a computer or a telephone function, but any thoughtful manager ought to be able to tell what makes those products easy to use. Usability has less to do with the physical sciences than it does with psychology.
I would argue, however, that The Design of Everyday Things can also help you refine your thinking about issues that go far beyond the stated scope of the book. I hope to touch upon some of these other issues in future posts (including a lesson that can be applied to public relations problems and a look at Norman’s observations on what causes people to make bad decisions.) For now, let’s take a quick look at the concept of affordances.
Affordances and Metaphorical Doors
Norman introduces the term "affordances" with a quick story about British Rail (now known as National Rail.) It seems they were having a problem with the shelters set up by the train tracks. When the sides of the shelters were made from glass, vandals would break the glass. When they replaced the glass with wood panels, the vandals would write on the wood. As Norman explains it, the materials not only allow, but also suggest, different uses. Glass affords breaking. Wood affords graffiti.
Affordances can also have positive and intentional outcomes. To revisit the issue of doors that you pull when they were meant to be pushed, that problem can be solved by affordances. If the door has a push bar on it, then the user can only push on it. The hardware affords pushing.
In industrial design, affordances are an important way a designer can influence the user’s behavior. This concept can be a useful touchstone in areas that have nothing to do with user-centric design. Ever since I first read The Design of Everyday Things (back in the mid 90s), I’ve been looking at the world in terms of affordances. Customer behavior (good and bad) doesn’t happen in a vacuum. Instead, it is a result of the decisions companies make.
British Rail obviously didn’t produce an instruction manual for their passengers that explained the best way to vandalize their shelters. The affordances of the material did that for them. Similarly, businesses are constantly in the process of silently but persuasively training their customers to behave in certain ways. The same affordances that affect designers and engineers also come into play every time a company makes a decision that is in any way observable by the consumer. For example, consider the trend of holiday sales that happen early in the morning on the day after Thanksgiving. These sales are the result of a series of choices the retailer makes about pricing (“20% Off!”), the merchandising mix (this many units of this particular model TV), and marketing communications (it’s a “Door Buster Sale!”) Design and engineering never enter the picture, but affordances do. That's why “Door Buster Sales” can end in actually busted doors. The retailers are unintentionally training their customers to push, shove, and even trample their fellow customers. Because retailers fail to consider all of the affordances created by their plans, they influence their customers in undesirable – and sometimes tragic – ways.
Norman asks you to take a closer look at the visible properties of products, but I think once you do, you’ll also start to notice the non-tangible aspects of your interactions with your customers, too.
Further Reading: The Design of Everyday Things by Donald A. Norman