Usability - What is it?

What Usability Is

Have you ever:

• Bought something that was so complicated to use that you gave up on it and bought something else to replace it?
• Tried to find something online and gotten hopelessly lost and confused?
• Found a site or product so easy to learn, easy and fun to use, and effective that you told all your friends about it?

These are all faces of usability.

Usability is a measure of the quality of a user's experience interacting with a product or web site. It is about users' ability to do what they want and need with the product or site. It evolved from the psychology of human factors and its focus on users and "user-friendly" products.

Human factors engineering is a crossover discipline that combines psychology, engineering, computer science, and software engineering to explain how people behave in the real world. Based on research, human factors engineers try to design systems and products to fit people, rather than the other way around, because it is easier to design systems than it is to change people.

The user-centered approach to design and assessment focuses on the mindset of target users. This means measuring:

• users' prerequisite knowledge and skills
• users' goals and objectives (which are often different from, and in some cases in opposition to, that of authors, designers, and/or programmers of a product or site).
• users' reactions to being lost, frustrated, or unable to accomplish their goals.

What Usability Testing Can Reveal

Usability testing methods can yield information about:

• How users carry out tasks.
• The errors users make and the criticality of those errors.
• When, where, and why users get frustrated or confused.
• How quickly and successfully users accomplish their goals.
• How satisfied users are with their experience.
• Possible solutions to problems users encounter.

Why Usability Testing is Worth Doing

Usability testing can reduce design and development costs and increase user satisfaction and sales.  Done early in the design and development process it can:

• Save money by exposing design flaws before expensive models have been created.
• Yield valuable information and lessons about one aspect of a product or site that can be applied to other parts of the product or site.  For example, the navigation and organization of a web site’s Home page can be tested before all the content and navigation for the rest of the site is developed.
• Make it easier and less costly to make any necessary changes.
• Make it more likely that needed changes will actually be made.
• Reduce the frustration of designers and developers caused by the need for rework.