Quantitative defects management in iterative development with BiDefect

Iterative development methodology has been widely adopted in recent years since it is flexible and capable of dealing with requirement volatility. However, how to quantitatively manage iterative projects, and in particular, how to quantitatively manage defects across multiple iterations, remains a challenging issue. In this article, we identify three main challenges of quantitative defects management in iterative development in a leading Chinese telecommunications company (named ZZNode). The three challenges are: identifying appropriate ‘control points’ in each iteration, selecting appropriate measures and corresponding measurement methods, and determining the ‘sweet spot’ amount of effort for performing testing and defect-fixing activities. We propose a process performance Baselines based iteration Defects management (BiDefect) method to address the three challenges. We also report an industrial experience where several iterative development projects of ZZNode successfully applied the BiDefect method in initial estimating, analyzing, re-estimating, and controlling number of defects and defect detecting-fixing effort. In addition, we provide the evaluation of using BiDefect method, and discuss the benefits and lessons learned from BiDefect and its application. Copyright © 2009 John Wiley & Sons, Ltd.