Managing Requirements Change the Informal Way: When Saying 'No' is Not an Option

TL;DR

This paper explores how requirements change management often relies on informal processes in practice, contrasting with traditional formal models, and proposes a new model that captures both informal and formal changes.

Contribution

It introduces a novel model of requirements change management that accounts for informal practices observed in real-world, globally distributed projects.

Findings

Informal requirements changes are pervasive and unavoidable.

A parallel informal change management process is necessary.

The proposed model better represents real-world requirements change dynamics.

Abstract

Software has always been considered as malleable. Changes to software requirements are inevitable during the development process. Despite many software engineering advances over several decades, requirements changes are a source of project risk, particularly when businesses and technologies are evolving rapidly. Although effectively managing requirements changes is a critical aspect of software engineering, conceptions of requirements change in the literature and approaches to their management in practice still seem rudimentary. The overall goal of this study is to better understand the process of requirements change management. We present findings from an exploratory case study of requirements change management in a globally distributed setting. In this context we noted a contrast with the traditional models of requirements change. In theory, change control policies and formal processes are considered as a natural strategy to deal with requirements changes. Yet we observed that "informal requirements changes" (InfRc) were pervasive and unavoidable. Our results reveal an equally 'natural' informal change management process that is required to handle InfRc in parallel. We present a novel model of requirements change which, we argue, better represents the phenomenon and more realistically incorporates both the informal and formal types of change.