PDF of this tutorialIn an increasingly competitive marketplace, those products and services that do not meet customer needs fail. Ease of use is a real user need and most product reviews, whether in consumer magazines or professional journals, usually compare products based on their usability. Research also shows that about 50 percent of the code in new software applications is devoted to the user interface, making it a significant cost component. Finally, applications have become increasingly complex—and delivering this increased complexity while maintaining ease of use is a challenging endeavor.
The importance of usability will vary from product to product. For safety-critical applications such as nuclear power-station management or air-traffic control, usability is crucial. Where a high value is placed on productivity, or perhaps a high cost is associated with human error (such as a financial dealing room or telecommunications network management center), usability is essential as well.
In marketing terms, where significant additional revenue will be generated from increased usage (for example, telephony services), usability is also a priority.
