Abstract
Usability is an important quality attribute for information technology (IT) applications. However, integrating usability design and evaluation as an integral part of the development processes in information technology development organizations is still a challenge. This chapter gives an overview on the usability cost-benefit analysis models and provides some example cases of the importance of usability. These models and cases can be used by usability professionals to motivate the organizational management to provide resources for usability work and to integrate usability work as part of the development process. The target audience for this chapter are professionals and researchers working in the field of IT, managers in IT development organizations, as well as managers in organizations acquiring and using IT.
TopBackground
Usability is defined as one of the main quality attributes for Information Technology applications, software products, information systems and online services (Marghescu, 2009). There are many international standards and recognized definitions of usability and user-centered design, which all have different focuses (Marghescu, 2009) First international standard referring to the usability defined it as the capability of the product to be understood, learned, used by, and attractive to the user, when used under specified conditions (ISO 9126). The second international standard defining usability is the standard ISO 9241-11, where usability is defined as being 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 (ISO 9241). The third common usability definition is by Nielsen and Schneiderman, who define usability as consisting of five quality components: learnability, efficiency, memorability, errors, and satisfaction (Nielsen 1993, Schneiderman 1998). Usability can be achieved through a user-centered design process, usability activities (e.g., usability testing, paper prototyping, heuristic evaluation), and having an overall focus on usability issues through the entire development process (c.f. Rajanen et al. 2017, Rajanen & Rajanen 2017). Furthermore, since the turn of the millennia, the concept of user experience (UX) has been introduced to take into account the emotions and attitudes of user about using a particular product, system or service (ISO 13407, Marghescu 2009).
Key Terms in this Chapter
User-Centered Design: Iterative and incremental process for designing and developing systems with good usability.
Usability Cost-Benefit Analysis: Comparing the costs and benefits of usability improvement activities in order to motivate investing to usability improvement.
Usability Improvement: Measurable improvement in usability of an Information Technology application, product, software, system, or service, when compared to previous version or to competitors.
Cost-Benefit Analysis: Making an investment decision based on the estimated costs and benefits of the planned activity.
Usability Work: Planning, design, and testing activity, which aims to improving usability of an Information Technology application, product, software, system, or service.
User Experience: Experience of an individual user in terms of ease and pleasantness of the use of an Information Technology application, system, or service.
Usability: The extent to which an Information Technology application, product, software, system, or service can be used easily, can be used without errors and can be learned easily by the users.
Usability Cost Justification: Motivating investing to usability improvements by showing that benefits of better usability are greater than costs.