Every dollar invested in usability engineering returns between two and 100 dollars

Though officially retired Deborah Mayhew generously and graciously contributes her UX wisdom and insight to some of Clarity’s best website design projects. Her own website leads with this very neat summary of what Usability Engineering is, why it matters and how it’s done. – Mitch Anthony

Usability Engineering – What?

Usability Engineering is a methodology for optimizing product usability during the development process.

In the case of traditional or web-enabled software applications or intranets, Usability Engineers work primarily with Business Analysts and Developers to achieve usability – ease of learning and/or ease of use – for end users.

In the case of websites, Usability Engineers must collaborate with Graphic Designers, Branding Experts and Developers to achieve business goals by optimizing a whole website User eXperience (UX).


A good website UX is like a good marriage.

Sex appeal and chemistry are necessary to kickstart a partnership – in a website UX, that’s achieved through appropriate and appealing Graphic Design.

Then, to sustain engagement as the partnership is explored, shared core values must be discovered and trust must be established – in a website UX, that’s accomplished through effective Branding and messaging.

Finally, to support commitment in the long term, reliability, consistency, predictability, effective communication and great teamwork must be established and maintained – in a website UX, that’s accomplished through Usability.

For some examples of usability guidelines in practice, see Sample Usability Guidelines for the Web.

Usability Engineering – Why?

It has been estimated that every $1 invested in usability engineering returns between $2 and $100. (Pressman, R. (2005). Software Engineering: A Practitioner’s Approach. Boston, MA: McGraw-Hill Higher Education.)

On websites, Usability helps capture competitive edge, increase conversion rates and maintain customer loyalty.

On desktop software, usability decreases customer support costs, costly user errors, and training costs, and increases user productivity.

For some concrete examples of the benefits of usability, see Bottom Line Benefits of Usability – A Sample.

Usability Engineering – How?

There is a structured process for achieving usability in user interface design. Like the the underlying product development lifecycle it must integrate with, it consists of an iterative process involving Requirements tasks, Design tasks and Evaluation tasks.

A variety of techniques, ranging from highly rigorous to very quick-and-dirty, are available for each task in the lifecycle.

The overall usability engineering lifecycle can be adapted to virtually any underlying development methodology.

While employing the full usability engineering lifecycle with the most rigorous techniques will minimize risk and optimize results, usability engineering techniques can be applied in isolation anywhere along the product development lifecycle and provide measurable improvements in usability.

If you want to understand and employ best practice UX you want to read Deborah’s own epistle: The Usability Engineering Lifecycle: A Practitioner’s Handbook for User Interface Design.


Header image from BrainStation.

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