Summary

The purpose of the specification review is to assess the correctness, completeness, and quality of the requirements specification. The review also gives you an opportunity to measure the value, cost, and risk attached to building the product, and to assess whether it is worthwhile to continue development of the product.

Consider the model shown in Figure 14.8. It provides a composite measure of the overall worth of the product, or the worth of a product use case. Suppose that you have devised a suitable scale for each axis. The low end of the scale is at the intersection of the axes, and the high end is at the extremities.

Figure 14.8.

Each axis represents one of the factors that determines whether the product is worthwhile. The size/cost axis can be assessed using function points or some other size measurement; it represents the cost of construction. The priority axis represents the value placed by the stakeholders on the product. The risk axis represents the severity of risks determined by the risk analysis activity.

Rank the risk, the size of the product or the effort/cost to build it, and the priority along the corresponding scale. What does the profile look like? If you have high scores for effort and risk, but a low score for priority, you should consider abandoning the product: The benefit from having it is outweighed by the risk and effort required to build it.

You can use the same model to compare the desirability of individual requirements, clusters of requirements, or product use cases. This type of analysis is helpful when your requirements cannot be met within the constraints (usually time and budget) and you are trying to decide which ones should have priority.

The products you would like to build are those that score highly on customer value and low on the other scales. You will not often see this nirvana-like state, but take note of whether the profile of your product indicates that it is one to build or one to avoid.