Usability

Digital Marketing - Study Notes:

What is usability?

One of the key factors that research will need to inform and assess is usability. This is another term which, like UI, can often be misused as an interchangeable term for UX. Usability is just one facet of an overall user experience, and a fundamental one.

“Usability: The extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency, and satisfaction in a specified context of use.” This ISO definition is taken from a dedicated international standard, ISO 9241-11 from 1998, Ergonomics of Human-System Interaction Guidance on Usability.

Just as UX is not UI, usability is not user experience. Usability is a by-product of designing in a user-centered manner. As noted by Jared Spool of User Interface Engineering, one of the world’s leading usability research training and consulting firms, usability asks whether a user can accomplish their goal whereas UX asks whether the user enjoyed the experience.

Usability promotes adoption and use

Usability is a crucial characteristic of any website or product.

The Diffusion of Innovations by Everett Rogers was published in the 1960s, and studied how innovations are new products were adopted and spread. The insights in the book were tested in more than 6,000 research studies and field tests, and they sit amongst the most reliable in the social sciences. The research elicited five principles or heuristics.

Rogers discovered that if an innovation or new product failed, it was likely to be down to one of the five factors identified in the book. Amongst these is ease of use, or what we now call usability. In short, if usability is missing from a product, the likelihood of rejection by users is increased. Usability can be tested, and usability testing is the single most effective way of assessing the usability of a website. Usability testing will fall into one of two categories, formative and summative. These terms originate in educational theory but are completely relevant to usability.

Types of testing

There are two types of usability testing:

• Formative testing: This can fall into the category of research for insight or research for validation. For instance, formative usability testing might be carried out on an existing website prior to identifying the areas of focus for a redesign.
• Summative testing: This takes place after a product or service has been launched, for assessing whether a website is performing as expected, or it might be carried out on prototypes during the development stage.