CONCLUSION

The IWISS model extends the work of Koufaris (2000) and others by providing and validating a nomological network of factors based on motivation and flow theory and the Garrity and Sanders (1998) model. One of the objectives of this research project was to compare the IWISS model to TAM. In the IWISS model, Perceived Usefulness is expanded into two closely related but separate dimensions – Task Support Satisfaction and Decision Support Satisfaction. The two dimensions provide additional precision and explanatory power that is helpful to both system designers, who want to design specific support features, and for researchers, who wish to evaluate the system's impact on Task Support or Decision Support Satisfaction (Figure 5).

An important goal of our research was to understand why users find web systems acceptable and useful, and indeed this is important for both researchers and practitioners involved in web-based systems development. From a practical standpoint, systems that are judged successful become a part of the organizational decision making framework and or part of the organization's system structure and processes. Additionally, IS success models are used by researchers who wish to build models and enhance our understanding of the factors that generate successful systems. A by-product of this empirical research is the development of normative guidelines that will then be used by practitioners. It is thus imperative for IS success models to be both valid and precise enough to be useful for developing practical guidelines.