The coming of the Apple is the buzz of the moment. Apple is the champion of making things simpler, but have they gone too far with the apple watch and made it too simple.
One click bonanza
The received wisdom in new product development is that you should take out steps, and continually simplify the product. This is what amazon did with one-click and this is what apple did with [insert your favorite Apple product here]. The reason is that it increases usability.
But sometimes the simplification meets a point where it doesn’t improve usability any more. With any product you will have some measure of complexity. Complexity is conventionally conceived as the number of possible states the system can have. So, roughly a measure of complexity is the number of variables a user can choose between and the number of states they can assume.
Some products are the antithesis of the amazon One-Click. Microsofts office suite has heaps of functions that are never used. Other products like SAP have a lot of different screens with a lot of functions, which make them difficult to use. But the reason that these functions are there is often that users actually need these functions, so for them they are necessary. If you take a way that functionality you will make the user interface more simple, but the complexity of the task you wish to do remains, only now, because of the too simple interface, it is even more complex than it was before. This is what we could call residual complexity, that is, the complexity of a task that is not supported by the tool.
Let me give you an example of high residual complexity. We bought a dishwasher called something with one-touch (perhaps inspired by amazon?) where indeed there was only one button. Actually at the face of it good thinking: Simplify to the core of the problem. What do I want to do with a dishwasher? make it wash my dishes. That works very well. Under normal circumstances. That is, until I discovered after it had been installed that, it just didn’t work. Not much you can do with one button then. I called the store and they had me push some sequences on the button to do diagnostics. Suddenly I found that the dishwasher was stuck in Turkish language. A language I am not intimately familiar with. What to do when you have only one button?
Finally it was back to the original language and an operator came on site to fix it and it worked. Now we were happy until the dishwasher had finished its washing cycle. For some reason, the product manager or whoever was in charge thought it would be nice if the dishwasher played “Ode an die Freude” from Beethoven’s 9th symphony. I love that piece and especially the ode, but not when it is played in a 15 second melody sequence with clunky 8 bit soundgenerator and repeated three times. Now I wanted to turn it off, but what to do with only one button?
One click communication
To illustrate it further lets take the simplification to its extreme. Take a keyboard on a computer. It has about 50-60 keys. They can be on or off. That leaves us with a product with 100-120 different possible states (not counting combinations, since a keyboard records only one stroke at a time). If you would like to simplify this maximally you could introduce a One-click concept where the keyboard had only one key that could be on or off. We just reduced the complexity of the user interface with a factor of 100 or more popularly we made it a 100 times more simple.
That, however, has been done centuries ago (literally). It’s called a telegraph. The telegraph illustrates clearly the problem of residual complexity, because in order to carry out the necessary tasks with a telegraph (communication) where there is only one button, it shifts the complexity from the user interface to the task: you need to learn morse code in order to use it!
That means when there is an inherent task complexity you cannot simplify the user interface beyond a certain point if the goal is to increase usability.
Residual complexity and the Apple watch
Now let’s return to the Apple watch. As compared to a watch, the Apple watch is not more simple. Quite the contrary. On the other hand compared to a smartphone it is simpler. And many, including Apple compares it to exactly that. You can do many of the same things on the Apple watch as you can on the iPhone.
For example you can read and reply to messages only, there is no keyboard. So, if you want to reply you have to choose a preconfigured reply or dictate a reply.
You can read an email there, but if it is longer than a short message you will have to scroll incessantly. You can also listen to music, but what if you want to search for a song? You can look at my calendar, but what if the entry is more than 15 characters or you want to move an appointment?
All of these examples are examples of residual complexity. Could it be that Apple just made it too simple? Could it be that Apple just built a new telegraph for your iPhone?
Photo by Clif1066 @flickr under CC license
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