It provides a divide-and-conquer approach to requirements analysis since the developer can focus on one part of a system at a time. A use case meets a specific business goal and thus the use case allows the developer to analyze requirement, one business goal at a time. An example is the use case "Buy Learning Materials". This use case spells out clearly the steps a Parent role takes to acquire learning materials for a Child role. Therefore, a use case provides a clear direction to a system developer.
A use case is reusable because of the rich view it provides. A use case will therefore help systems developer not only during requirements gathering but also as a guideline during development. It can also form the basis of systems documentation much latter. The use case diagram for LSS above reveals the different components of the system under development allowing the systems developer to develop the system in a modular manner. He can start with the use cases that are considered more urgent/important by the users.
Use cases provide alternative scenarios thus enabling a systems developer to accommodate many behaviors of a system. ...Show more