Instability of Requirement Set Late in Project Lifecycle
This guideline describes how to measure and use the Instability of Requirement Set Late in Project Lifecycle metric.
Main Description

Overview

If the requirement set is unstable late in your project lifecycle, this reflects the possibility that a project is diverging from delivering on its needed capabilities with quality and reliability. Typically, this uncertainty is an indication of churn, which is not desirable.

This measure helps bring attention to ensuring that requirements are stable earlier in the project, to reduce the impact of late discovery.

Instability in requirements late in the lifecycle is often very costly and high-impact, given the investment that may have been made in designing, implementing, and testing requirements that may no longer apply.  

Measurement Method

Percentage of new, modified, and de-scoped requirements during time i.

This measure applies separately, or combined, for each level of requirement. 

Measurement Analysis

A good way to monitor the instability of the requirement set is with a line chart that shows the percentage change through the lifecycle. Any increase in the instability of requirements in the latter half of the lifecycle is a warning that their is a poor understanding of business needs or software requirements, and this may impact your team's ability to deliver the needed capabilities with quality and predictability.

More Information
Supporting Materials