Cost-Justifying Usability: An Update for an Internet Age

Chapter 2: User Interface Design's Return on Investment: Examples and Statistics

Aaron Marcus Aaron Marcus and Associates, Inc.

2.1 Introduction: What Do We Mean By The Return On Investment Of Usability?

Making computer-based products (and services) more usable is smart business. Usability increases customer satisfaction and productivity, leads to customer trust and loyalty, and contributes to tangible cost savings and profitability. User interface (UI) development is part of a product's development cost anyway, and it pays to do it right.

Most software and Web site development managers view usability costs as added effort and expense, but more commonly the reverse is true. Because the first 10% of the design process, when key system-design decisions are made, can determine 90% of a product's cost and performance, usability techniques help keep the product aligned with company goals (Smith and Reinersten, 1991). Usability returns many benefits (return on investment [ROI]) to products developed for internal use or sale (Lund, 1997; Mayhew and Mantei, 1994; Wilson and Rosenbaum, Chapter 8).

The following are some of the benefits that drive internal ROI:

  • Increased user productivity

  • Decreased user errors

  • Decreased training costs

  • Increased savings from making changes earlier in design lifecycle

  • Decreased user support

The following are some of the benefits that drive external ROI:

  • Increased sales

  • Decreased customer support costs

  • Increased savings from making changes earlier in the design lifecycle

  • "Reduced cost of providing training (if training is offered through the vendor company)" (Mayhew and Mantei, 1994, p. 126)

  • Increased perception of value of company by stakeholders

Usability also plays a role in the public's...