Data Driven Decisions

Chapter 20Use Cases and Behavioral Diagrams

Another useful tool in systems engineering that executives can use to understand which intangible assets matter the most is called a use case and behavioral diagram. Use cases refer to the basic functions that a customer or stakeholder expects a system to perform. You might purchase a toy expecting it to provide some level of constructive playtime, and maybe there is a light feature, vocal, or musical component. The value of the feature is in how the user experiences it. We call these basic expectations the use cases. Unsurprisingly, the use cases that matter the most are generally the ones that matter the most to the user.

A behavioral diagram (see Figures 20.1 and 20.2) helps us understand how a use case, an initial condition, interacts with an operator's decision, resulting in a new exit condition. So, for example, if a child is able to change the outfits of the Little Chef, and several children play within this same space, and each child changes the state of the toy, the toy will find its way to a new exit condition.

Figure 20.1

Figure 20.2

Diving deeper, system use cases essentially describe how a system user, actor, or stakeholder uses the system.

Use cases are not written in a specific way like requirements. Use cases ...