4.1 Introduction

This chapter focuses on the merits of cost-benefit analysis of usability engineering with a new emphasis on Web applications and services. It covers the financial benefits resulting from usability engineering, cost-benefit analysis and its relationship to business cases, the different published cost-benefit methodologies, and anonymous case study data. Professionals working in usability engineering have recognized for some time the need to communicate the cost benefit and value of this work more effectively. More than a decade ago, Chapanis (1991) discussed the human factors profession's need to improve its communication of the content and value of human factors and usability engineering. Curtis (1992) called on usability engineers to make better business cases to executives about the effect of a product's user interface on the market and to search actively for human factors opportunities that will have visible financial impacts.

Toward achieving successful integration of human factors considerations in development projects, I have found it important to address project-management concerns regarding time, personnel, and financial resources required for human factors work, as well as the resulting economic benefits from its inclusion in projects (Karat, 1990, 1993b, 1994). In 1994, the first edition of Cost-Justifying Usability became a seminal book on the topic. The collection of information in the book guided human-computer interaction (HCI) professionals, and the data and methods in the book have been used and quoted around the world.

After publication, I received several e-mails and phone calls each month...