By Arathi Sethumadhavan
I just finished reading Philip Kortum’s latest book on Usability assessment: How to measure the usability of products, services, and systems. This is a very comprehensive book for beginners to understand what usability assessment is, why it is important, and the techniques to perform a usability evaluation.
Below are the common myths on usability that the author discusses. I am sure several of you reading this have heard or experienced at least some of these.
- Usability assessment is complete if the product developers can use the product:
- Programmers, though skilled in developing the most robust code and algorithms often times fail to consider the expertise and skills of the actual users of the product. Therefore, they conclude that if they are able to use the system, the end users will have no trouble using the system as well.
- Usability assessment is just common sense:
- The author gives the example of fire trucks, which are usually painted red. The reason behind using red is the misconception that red can be easily detected. However, evidence from human perception studies have shown that red is one of the most difficult colors to detect for the human eye, especially at night. It is therefore important to make sure that design decisions are backed by empirical evidence and not by “common sense”.
- Highly trained users will be using the product and hence no usability assessment is needed:
- First, a well-designed product is one which requires no training and therefore claiming that the product users will be highly trained does not speak very much about the product. Second, even the most highly skilled users make use errors.
- The system is fully automatic and hence no usability assessment is needed:
- Even the most automated system requires human intervention at some point. There is in fact a plethora of human-automation research that demonstrates the importance of keeping the human operator in the decision-making loop and designing emergent features that communicate messages to the operator. Therefore, assuming that automated systems require no usability assessment is a misconception.
- The system is not mission critical and hence no usability assessment is needed:
- It is equally important that consumer products undergo usability evaluation. Time is of utmost value to a consumer and a product that requires a lot of steps can cause user confusion and frustration and can impact the adoption of the product in the marketplace.
- The system involves off the shelf components which have been evaluated separately and therefore the system requires no usability assessment:
- It is important that the interaction of the users with the entire system is assessed versus interaction with just the individual components of the system. Each system may be usable individually but may have employed conflicting design principles that may confuse users. For example, a color may mean something in one system component but may signify a conflicting theme in another system component.
- There are no users who are stupid enough to use the product wrongly:
- The part of the statement that says there are no stupid users is accurate. However, users can certainly use the product in a manner that was not intended by the product designer. Every user tries to use a product with a goal in mind and based on their past expectations of how a product would work. Problems arise when the mental models of users are inconsistent with that of the product developers.
Usability assessments can reduce use error, increase safety, increase task efficiency, increase user satisfaction, and provide financial benefits.
I would like to conclude with a statement that the author makes, which is “Good usability is invisible”.