Advantages of Prototyping
Prototyping has the following advantages
Better definition of user needs. Because of intensive end - user involvement, prototyping usually results in a good definition of user needs.
Higher user involvement and satisfaction. When user requirements are met, the results are greater user satisfaction and less risk that the AIS will not be used. Early user involvement helps to build a climate of acceptance rather than skepticism and criticism about the new AIS.
Faster development time. It takes only a few days or weeks to get a prototype system up and running, which allows users to immediately evaluate significant changes in the way business is transacted. In contrast, it may take a year or more under the traditional approach before the new system can be evaluated. John Hancock Mutual Life Insurance developed the prototype of an executive information system in only one month, as described in Focus 19 - 2.
Fewer errors. Because the user experiments with and uses each version of the prototype, errors are detected and eliminated early in the development process. In addition, it is much easier to identify and terminate an infeasible AIS before a great deal changes of time and expense are incurred.
More opportunity for changes. Under the traditional SDLC approach, the design team is responsible for identifying AIS requirements the first time around. These requirements are then frozen so that the team can complete the AIS. With prototyping, users can continue to suggest changes until the system is exactly what they want.
Prototyping: The Third Dimension
An architect develops two - dimensional blueprints that show how a custom home will look. However, a look at the third dimension, walking through the home, lets you actually see the rooms and get a feel for the layout. Creating customized software provides a similar challenge. Users must try to visualize the look and feel of their software from written specifications. Prototypes help users who have ideas or plans but do not know how to turn them into reality, as well as users who have a problem but do not know how to begin solving it. A prototype lets them walk through the proposed system and experiment with its look and feel before committing to the expense of application development.
John Hancock Mutual Life Insurance Company was dissatisfied with the traditional development process: determining user specifications (getting information from high - level executives was especially difficult), writing them up, developing the system, and presenting it to the end users. The typical reaction from a user was, "I may have said that this is what I wanted, but it isn't."
To counter these problems, Hancock used a prototyping approach to develop an executive information system (EIS). The EIS was needed because the company was dissatisfied with its inability to obtain data quickly and easily from the existing system.
Hancock formed a team that included systems development consultants from IBM, user representatives, systems analysts, and programmers. The prototyping process was highly interactive, and the continual involvement of the end users eliminated a great deal of misunderstanding. The programmers on the team stared programming almost immediately. They prepared sample screens for the first interview session with users. The development staff sat down with users and showed them how the system would work. Users were then given a chance to try the screens. Almost immediately, users could determine if what they said they wanted was really what they needed.
The result was a prototype for an EIS that took only one month to build. The prototype allows top management at Hancock to access and query current and historical financial data and measurements. Top managers who had been skeptical when the project began were impressed by how much the team was able to accomplish in a single month.