Editor’s note: Michael Maddox, PhD, CHFP, is a senior scientist for HumanCentric Technologies. The Human Factor is a regular feature in LTW.
_______________________________________________________________________________________I spent most of the day in Atlanta a few weeks ago. I flew into town in the morning and back out in the early evening. Prior to my departure, I had to go through the security process at the Atlanta airport. It is really something to behold.

I began the process by entering one of two intertwined serpentine queues. It reminded me of Disney World on acid.

After walking back and forth in the maze for some period of time I arrived at the document checking area. From there, I was ready to enter another queue that leads to the real security area — with the metal detectors. However, before I actually got to the point at which I was assigned to an individual metal detector queue, I passed a glass case in which banned items are displayed.

By the time I reached the display case, I was thoroughly bored and ready for any diversion. Performing sort of a mental checklist of the displayed items, the imagined soundtrack ran something like this–“box cutters, yeah, butane lighter refills, yeah, propane torches, OK, firecrackers, well sure, gas camping lanterns, yeah, I could see that, leaf blower, uhhhh.”

LEAF BLOWER? Yes, on the bottom shelf of the display cabinet, positioned prominently for all to see, was a full-size, gas-powered leaf blower.

How in the World —

The guy in front of me in line turned to me with a very quizzical look on his face. Than about 10 of us in line just started laughing and wondering what the heck a leaf blower was doing in the display case.

The result of our reasoned discussion was that there are only two plausible explanations for that leaf blower. First, the TSA might actually have a sense of humor and understand that people herded like cattle might need a mood lightener. The consensus was that this explanation was not too likely. The second explanation, which seemed more plausible to the group, is that somebody, at some point in time, actually tried to board an airplane while carrying a leaf blower. Keep in mind that by the time a person is able to view the display case, they have passed through at least three points at which TSA workers have been able to see and talk to them. Is it likely, or even plausible, that a traveler has inadvertently carried a leaf blower (or a camping lantern, etc) past all that scrutiny?

Anticipation Is Better Than Reaction

Which brings me to the point of this article (and I know you were wondering when I would get to the point). Whenever you deal with human behavior, you should expect to see the widest range of actions you can possibly imagine — and beyond.

In the human factors profession, we deal with such wildly varying, some might say “weird”, behavior every day. Fundamentally, that’s why we push for usability testing of products, processes, and systems. We know that no matter how much we try to intuit what people will do in a particular situation or with a specific product, we’re just not able to figure all the permutations.

Apart from the leaf-blower-carrying type of extreme behavior, we’re often surprised by even the most mundane interactions with products. Even with all the experience and data amassed by human factors researchers and practitioners, it is simply not possible to put us exactly in the minds of every potential product user. — and anyone who tells you they can do that is blowing smoke. I’ve been a human factors practitioner for over 25 years and I’ve run many tests in which users interact with new products, software applications, etc. I’ve never run such a test in which I haven’t been surprised by something a test participant did.

The natural tendency is to get engineers, software people, marketers, product managers, and maybe a human factors person in a room and decide how people are going to interact with a new or proposed product. After all, we’re all smart people. We should be able to figure this out. And therein lies the fundamental problem. We’re all smart, highly motivated people who are probably completely disconnected in every way from the people who will use the product. I’ve always maintained that a group of sufficiently smart and motivated people can convince themselves of anything. The high frequency with which this occurs supports that contention.

In the human factors profession, our way of addressing this issue is to try and not over-think the issue. Instead of deducing how users will interact with a product, why not simply put them in front of it (or a simulation of it) and see how they interact. We’re often edified by the results of such testing. We’re also often chagrined, surprised, and mystified. But it’s better to be surprised before the product goes out the door. It’s a lot easier to fix before it goes into production.

Don’t discount the possibility that someone will try to carry a leaf blower on board.

HumanCentric: www.humancentrictech.com