Usability quality

As software companies face ever-increasing competitive pressure through the process of development of new applications, they need to define, understand and focus on their core competencies. A main contributor to a company�s success is the quality of it�s product lines.� The term Software quality refer to various perspectives, including reliability and usability.

Software companies prefer to prevent bugs rather than to fix them after they are already introduced to the market. The reason for this is that the expenses of problem fixing after the product is already installed at the customer site are very high, and the costs of loosing the market are immeasurable. This attitude characterizes all software design, and particularly user interface design.

Industry standards are not enough

The common rules for user interface design are based on the means provided by popular development tools and on industrial standards. The tools and the standard facilitate the acquaintance with new software products. However, they do not contribute to the main usability issue, namely, to serve the software features that correspond to a user task, according to the user�s expectations. In fact, the most important usability issues are not even in the scope of industry standards.

Not all human factors are well understood

Recently, more and more companies consult experts in ergonomics (human factors) as early as at the specification stage. However, many of the problems presented in a software product are overlooked even by professional user interface designers. Another limitation of consulting services is their costs. Not all software companies can afford to pay for these services.

Problems with traditional usability testing

Although the usability a software product is determined by design, the only means to verify that is indeed usable is by testing.

Traditional usability testing relies on observations of experts in software quality assurance during Alpha testing and on reports of the end users during Beta testing.

�     The limitations of Alpha testing

Typically, the persons who test software in Alpha testing are of technical background. Traditional testing, by persons of technical background, do not reveal many usability problems, especially those that characterize the first use of a new product. Eventually, they attribute the reasons for usability problems to the end user, rather than to the software design.

�     The limitations of Beta testing

In Beta testing, the end users are cooperative in reporting on those problems which prevent them from completing their tasks. However, end users are not likely to report on a problem if they find a way to work around it. Many usability problems are not identified even in Beta sites, because typically:

�      Users cannot repeat most failure modes

�      Users prefer to find ways to work around an operational error rather than� to report on it

�     Users consider operational errors their own fault, rather than design problems.

For these reasons, many usability problems are not identified through the whole product life cycle.

What is required for better usability testing

To overcome these limitations, large software houses raised special department, Usability labs, operated by experts in Human Factors engineering. In these labs, real users are observed by professionals, while they use the real product for completing real tasks. The analysis of usability problems involves various techniques, such as video recording and back tracking and methods such as using questionnaires and �think aloud�. Many of the usability bugs are found using these means.

The effectiveness of Usability labs

The operation of the techniques used in usability labs is very expensive and time consuming. Many developers of high functionality Windows applications, including small and medium software houses, are forced to compromise usability issues, because they cannot afford to pay for the services of usability labs. As time and budget resources are always limited, usability labs need to focus on the main problems and to ignore others. Eventually, many software products that were examined in usability labs, including main line products of the leaders in the software industry, suffer from severe usability problems.

Another limitation of the Usability labs is that they do not quantify the usability problems. For example, they cannot provide statistics on the total time wasted because of the user�s unintentional press of the Caps Lock or the Alt key.