Mental Models and Usability design

[#1]

I recently updated to iOS7….hmm...The new look and feel is certainly delightful, although, one particular thing really got me frustrated. While exploring Apple’s new eye candy, I was trying to delete an email from my phone by the usual way, which is by swiping my thumb from left to right. Obviously, I was expecting a delete button to show up. I tried once, twice and several times, it just wouldn’t do anything and the most frustrating part was that it opened the email instead of deleting it. At this point, I gave up and went into my setting to see if something was turned off…and nothing! Finally I decided to do a web search and AHAA!....They actually switched the whole interaction paradigm of deleting an email from swiping from left to right to now swiping from right to left.

This was the complete opposite of the model that I had carried in my mind for all these years. This was just a small example of a mismatch in the user’s mental model to the designer’s mental model which caused some degree of frustration and took some time and efforts in figuring out. In this instance, the learning curve was quite low, but what happens when there are so many things in an interface which throw you off because what you expect it to do, is not what it does in reality. This not only causes frustration but a repulsion effect and even the things that work well go un-noticed spoiling the whole experience.

A designer’s goal should be to keep the learning curve as smooth as possible. This is when the concept of mental models comes into play. A mental model is a person’s perception and an understanding of how something works based on prior knowledge and experience, it is based on beliefs not facts. These mental models are very loose and keep evolving over time; they cannot be visualized and often times aren’t accurate.

Today, we are constantly surrounded by different systems and interfaces that we have to keep adapting to. Although, these interfaces differ from one another, there are certain design standards that have evolved over time, which they all follow. People form a mental model of how these interfaces work. For example, one of the reasons why we place our Filters on the left side of the sheet in a QlikView application is because we are all used to the web where mostly the navigation panel is always on the left side. Leveraging these already formed mental models in our designs can be very useful in creating a seamless interaction pattern and creating a good user experience.

However, sometimes, it becomes necessary to challenge the standards in order to keep up with the changing technological landscape. This needs a seamless transition of the already formed mental models to new and evolved paradigms.  As we move slowly into the phase of designing QlikView applications in the 'Next' version, these considerations will become vital to ensure a smooth transition. The below mentioned design considerations can be helpful in achieving this -

• Providing subtle cues so that users don’t get lost
• Frequently used functions to be easily accessible
• Providing certain familiarity aspects in the new design which users can recognize easily
• Providing flexibility
• Always providing a feedback from the system to the user

More information on this topic can be found at http://www.nngroup.com/articles/mental-models/.