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Intuitive Design Is Hard

When target knowledge overlaps with current knowledge

There is a video going around on Twitter recently about two teenage boys who are asked to make a phone call on an old rotary phone. TLDR; they fail miserably.

The video is a prime example of how difficult it is to create intuitive design. There is no one real answer to what actually makes design intuitive. That all depends on your user and what they would consider as intuitive. And like in the video, the intuitiveness of a design can become outdated with time.

Let's first look at what the definition is of intuitive design. I like the explanation Jared Spool gives. It's when the target knowledge, the knowledge needed to use the design, overlaps with the current knowledge of the user. Or when the design has enough signifiers to bridge that gap without any significant mental effort by the user.

Take for instance a door handle. You've probably learned how to use a door handle long before you could even reach it. You've seen your parents or older siblings do it a million times but your just not tall enough to reach yet. Once your tall enough though, your current knowledge is enough to perform the task of opening the door.

Recently I had to turn the door handles of some of the doors in my house upwards because my youngest was able to reach them and we don't want him wandering onto the street in an unguarded moment where we didn't lock the front door. Suddenly there was this gap between my current knowledge and target knowledge, however small. I suddenly had to keep my hand in a different angle and the vertical motion to pull the handle down suddenly turned into a horizontal motion. But luckily there were enough signifiers. The handle still looked the same, it was just at a different angle. I knew that it would rotate the same direction. And I still had the knowledge of how the mechanism insure a door works that helped me in understanding how the angled door handle would work. My eldest boy had some more difficulty in bridging that knowledge gap.

But not all things are as common as a door knob. Especially digital products. Where door handles or door knobs haven't changed much since the 1800s, computers and the internet have only been around a few decades and have changed a lot. Digital products have often only been around for a few years and have already changed even more so. In this area the knowledge gap can be enormous. To make this gap smaller, digital products relied on metaphors; a resemblance to a physical object with similar trades. Only up until a few years ago skeuomorphic design helped in this. Apple did this like no other. Take their note app for example. It had a lot of visual cues it lended from an actual note pad. It even had this edge of torn paper at the top as if there were already some sheets of paper used and torn of. Buttons needed to look like buttons, like they afforded to be pushed down. Since a few years we've stepped away from skeuomorphic design in favour of flat design. I'm not going into the pros and cons of flat design, but the reason we could make that step from skeuomorphic to flat was partially because the knowledge gap was small enough. A flat button doesn't look anything like a real button, but it has enough of the trades of the skeuomorphic button that people can make the association quite easily. We're so accustomed to digital interfaces that nowadays we don't have to make the association with physical objects anymore. It's more about convention, how familiar users already are with certain patterns and their mental model, how they expect it to behave based on prior knowledge of similar products.

Before designing anything you should have an intricate knowledge of your user. What are these conventions your users are familiar with?

In case of the teenagers in the video clip, it's easy to say they have never seen a rotary phone before. At least one of the two does seem to recognise the horn for what it is.

It's also a fine example that even something as common and institutionalised as a phone can be unintuitive. At least, dialing a number on one can be. Designers should never assume their current knowledge is the same as the users' current knowledge. The thing you're designing may very well be less intuitive than you think. Creating something intuitive requires careful thought and plenty of research. Creating something intuitive is hard.