The Fagan Defect-Free Process

What is the Fagan Defect-Free Process?
Michael Fagan initially created the software inspection process for the purposes of reducing the number of defects that reach users, removing defects before testing so as to lessen the workload on overburdened testing operations, and making development projects both measurable and manageable.

As the industry has accepted and began implementing his well-known Fagan Inspection Process, Michael has realized that additional elements (that he had also put in place in his organization) are also required for successful implementation of this method. So, he created the Fagan Defect-Free Process - the only complete process that includes the necessary infrastructure to establish and maintain a defect-free process!

This process is composed of three interdependent components:

Formal Process Definition,
Fagan Inspection Process, and
Continuous Process Improvement.

FORMAL PROCESS DEFINITION is a method of defining the work process in terms that make it measurable and manageable by its users. The goal of this component is to reduce the number of defects injected in the first place. It also channels the developer's activity more effectively, enabling them to create their work products with less effort.

Your development processes already in place do not have to change - they are just made crisper and clearer through this process to ensure defect-free flow from marketing and requirements through development through to customer use. The whole organization involved in the development process finds that it helps them better focus their efforts and reduces rework.

Without our method of formal process definition in place, implementing inspections on their own are often doomed to less effective inspections (or failure) over the long term due to time pressure, neglect and lack of understanding.

FAGAN INSPECTION PROCESS consists of 7 operations. Naturally, it is formally defined. Its objectives are to:

Find all the defects in the work product that is examined, and
Find all the Systemic Defects in the process that created defects in the work product.

Inspections are performed on requirements, design (software and hardware), code, test plans and cases, project plans, quotes and proposals.

CONTINUOUS PROCESS IMPROVEMENT involves removing Systemic Defects from the work process as they are found by inspections or other operations in the life cycle. Successive iterations reduce the number of injected defects and increase the percentage of detection of those that are injected.

Systemic defects are the most costly forms of defects to an organization. Removal of these is critical to reducing costs and shortening the development life cycle.