rendermouse blog

Usability & Common Sense

I was discussing the MIT "Common Sense" notes with a friend, and I had some thoughts to share...

At my previous employer, HotelTools, we used real-world common-sense input from subject matter experts/employees to design the behavior of our app. How should the app behave? Ask the users, not the developers. Make the software predict the user's common sense behavior.

Common sense is the heart & soul of usability. Something is "usable" if it responds in a way I assume it would respond. If I get in a new car, it should go when I push the accelerator.

I form assumptions of consequence before I perform an action. If these assumptions are proven wrong, I get confused and may become more hesitant to make similar assumptions in the future in relation to the task. Common sense has gone unrewarded in such a case.

This also leads to the need for consistency, which is another huge usability issue. If your common sense was rewarded once, you would expect it to be rewarded in the future. If my hotel software accurately predicted that I wanted to check someone out of the hotel because I clicked on the name of a guest who was scheduled to leave today, my common sense was rewarded. Therefore, I presume that when I select a guest who is scheduled to arrive today, it will also assume that I want to check them into the hotel. If it does not, I will not be able to make a consistent prediction as to the results of my actions, and the software becomes more frustrating to me.

Try to anticipate your user's actions. If there is very large chance that they will always do a certain thing in a certain situation, default to that action and give them the ability to navigate elsewhere if they want something else.