6.1 Objectives

Arranged in your computer is a collection of use case documents, and each one describes a possible system component. This set of requirements may be discouragingly large. You must now select the best options identified during the Filled iteration and include only these in the project scope.

The Focused iteration clears a path through the paperwork and leaves you with clear project requirements. At the end of this iteration, you will have defined the system and will have gathered sufficient information to build a successful application.

The Focused iteration separates the essential from the nice-to-have . It is now that you decide what is important, what will be built, and why. You examine the business problem from the context of your proposed solution, and you make sure that the solution doesn't solve unnecessary problems. For this reason, the Focused iteration is a difficult one.

When this iteration is complete, the use case model will describe the users' interactions with the system. These interactions allow the users to solve the business problems that initiated this development effort. The deliverables you create during the Focused iteration give you a detailed understanding of the scope of the system as well as its complexity and the risks involved.

To build systems that fulfill users' needs, you must understand the essential core functionality and help them understand which functionality is necessary. You can eliminate waste by carefully examining the scope and thus reduce the system to its essentials. Removing functionality at this stage is a real money saver. You avoid the effort of prototyping, designing, reviewing, building, and testing the additional functionality.

The following sections describe the steps in the Focused iteration.