Bias and Mayhew have recently released an updated edition of their classic book, Cost-Justifying Usability. Given that the first edition was published prior to the widespread domination of the World Wide Web, this update is welcomeand perhaps even overdue. It includes four of the chapters from the first edition (all updated), plus 18 new chapters; the contributors are again prominent figures from the field of usability. If you are lucky enough to work for a company that completely understands the value of user-centered design methods, you may not find the book, or this review, useful. However, if you are like most usability practitioners, and from time to time need to justify the value of your efforts in the context of the overall product lifecycle, this book should be welcome and may become a handy reference.
According to Bias and Mayhew, we must begin to speak the language of business better, with "less usability evangelization, and more specifics on its financial value." By now, many of us are familiar with the basic ROI (return on investment) model for usability that quantifies the value of every dollar invested in up-front usability efforts over the lifetime of a design. This model is based on the idea that the cost of redesign increases the later in the development cycle a particular problem is discovered, and that a structured usability effort helps to detect problems earlier, when they are cheaper to fix. The latest edition of Cost-Justifying Usability illustrates how the strategic use of user-centered design methods lowers costs, with each chapter providing statistics and examples. It succeeds in "illustrating the value of usability when hard statistical and behavioral data are absent." While this edition broadens the scope of the first one and provides an emphasis on Web ubiquity and e-commerce, what many of us will find most useful is that cost effectiveness is approached in the context of a wide range of products, services, and perspectives.
Analysis Parameters and ROI
In our lives as user-centered design practitioners, we know that methodology matters. This also applies when cost-justifying usability, as each project has unique constraints that require unique methods. For example, when performing a cost/benefit analysis of a transaction system, the main cost/benefit concern is to measure gains in productivity, which are greatest when there are many transactions and many users. To show this, the authors document a case study in which a seemingly small productivity improvement (a half-second per transaction) has a major cost benefit when considered across the system's total usage: A half-second improvement considered over a year for 5,000 users who each perform 120 transactions per working day and earn $25 per hour is a savings of almost $500,000. This is a dramatic savings for a seemingly small improvement!
The approach of using transaction-based productivity metrics to cost-justify usability should be familiar to many. While it may seem difficult to apply this approach to websites or consumer software, examples throughout the book demonstrate that variations of this approach are applicable to product development in all businesses. The authors show how the costs of poor design can always be reflected back on the company selling and supporting such designs. Indeed, throughout the book, the cost/benefit that seems to occur most frequently, regardless of industry, is reduced product and support/training costs, and increased sales. The book has an example in which a broad view of the costs of a usability project (including costs of usability specialists, developers, and managers; the number of transactions per day; current error rates and recovery times; the expected system lifetime; and the costs of maintaining a usability lab) is compared with an equally broad view of company benefits (including reductions in training times, customer support costs, error rates, transaction time, and late design changes). The result? An ROI greater than 160 percent.
Since it is easy to argue with the basis of ROI calculations, the authors suggest that the benefits of a usability effort be estimated conservatively. If this is done, a strong ROI will be demonstrable even in the face of unforeseen circumstances, like stepped-up usability efforts by your competition, technology constraints, or natural and man-made disasters.
Distinct Business Model for the Web
ROI analyses have typically been performed to in-house software projects or desktop product-development contexts. Though the same approach can apply equally to e-commerce and websites, what distinguishes e-commerce and websites from new products or services is that on the Web there is often less clarity about just who you are designing for, a point Bias and Mayhew correctly drive home. "Web users come from a user population with unprecedented levels of diversity in terms of language, previous computing experience, education, disability, network connection speed, cultural identity, and a whole host of other factors that haven't been considered." ROI analyses based on efficiency improvements are further limited by the typical Web and e-commerce business model that generates revenue directly through advertising, and only indirectly through the quality of services delivered to some target audience. Nonetheless, the book still includes specific techniques for cost-justifying these kinds of projects. The following statistics speak volumes about the potential for cost-justifying usability on the Web:
- 65 percent of online shopping attempts end in failure because users cannot find what they are looking for. The majority of these users will not attempt to purchase from the site after a failure experience.
- Some 80 percent of application code maintenance, which requires a large chunk of most business budgets, is spent on unmet or unforeseen user requirements.
- More than 33 percent of users said they would make more purchases online if the website provided information and user control during the shopping experience.
- 20 percent of Web surfers said they would be more likely to share personal information if they felt the site was trustworthy.
- Repeat visitors to a website normally spend twice as much as new customers.
Insights from these statistics can also generalize to Web portals or sites designed specifically for employee or B2B productivity. Unpublished reports indicate that far too many portals are going underusedor even unusedregardless of whom they were designed for. For any Web-based application, usability techniques help to identify the application's users, to retain those users by identifying their needs, and to establish and build trust with them. Hence, it is quite clear that there is a strong ROI for usability. Since many are operating in a global marketplace, the book also shows how to extend these concepts to international markets, with a special focus on compatibility with different languages and cultures.
Monetary or Otherwise, Usability Is Valuable
The authors argue that the benefits of usability go beyond what is directly measurable. Good internal communication and corporate citizenship, which the book refers to as "social ROI," add value to a business in ways that may not appear to be monetary, but which are part of a company's future competitive value and product development. Techniques such as contextual analysis or task-flow diagrams promote "reuse" of code, consistent interfaces, a shorter systems development cycle, and better collaboration, all of which can lead to future savings. The book allows practitioners to connect the dots on issues that businesses would be foolish to ignore. One chapter makes the connection between Web accessibility and profitability obvious. In addition to the present benefits of accessibility, as society ages, the increase in market share that a more accessible website will bring can only grow, increasing the ROI.
"How and Where to Go About It"
While the first half of the book presents a strong argument for the cost-justification for usability, the latter half helps identify the best and most cost-effective usability techniques and the contexts in which they should be applied. For example, one chapter presents an in-depth discussion of the Rapid Iterative Testing and Evaluation (RITE) method, a well-formed approach to discount usability testing. This method decreases project costs by identifying and correcting design problems early, and increases the credibility of the usability effort by including management and developers in the evaluations. Several other chapters present a discussion of survey techniques, which is bolstered with statistics to show that surveys are a cost-effective way of obtaining insights from users. Some surveys are free, like the Software Usability Measurement Inventory; more sophisticated ones, like the website Analysis and Measurement Inventory, carry a monthly fee. One of the survey techniques illustrated in the book allowed for linking usability satisfaction directly to the business goal of product usage. The higher the usability-satisfaction metric, the more the product was used. This had a direct impact on more sales of the product. Similar benefits were illustrated with keystroke-level modeling, which is good for comparison across different versions of software. The costs and benefits were discussed in-depth with enumerated lists of each technique.
This new edition of Cost-Justifying Usability reminds us that sweeping demographic changes, including the fusion and proliferation of mobile devices with the Internet, mean that a steady stream of new products and services will appear on the market, and that usability will play a major role in distinguishing the successful ones from the flops. In addition to being a handy reference guide for practitioners, this book will likely become a standard textbook for students. If a criticism has to be found, it is that many of the crucial examples come from unpublished or "deidentified" projects or studies. While this is understandable, some of the examples could have been more forceful if they were identified. That, however, is just a quibble; this is a strong book that is timely for our field and the challenges we are currently and will continue to face.
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Reviewed by Stacey Sutton
About the Reviewer
Stacey Sutton is a usability consultant based in Indiana. Her expertise ranges from IT to electronic voting interfaces. She has served as a reviewer for the 2007 UPA conference as well a mentor for an award-winning design team. Stacey received her master's in HCI in 2005 and continues to do research and writing on issues relating to usability. Her website and blog are in progress, and she can be reached at firstname.lastname@example.org.
To submit a book review, please email Gerard Torenvliet at email@example.com
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