The Definitive Guide to Project Management: The fast track to getting the job done on time and on budget (2nd Edition)

It is vital to be crystal clear about what quality means in project management. It is very useful to know the generally accepted meanings of quality management, quality objectives, and quality management system. A slightly easier-to-remember definition of quality than the ISO/PMBOK one is 'conformity to requirements', which is a perfectly good definition for use in real-life project management^[4].

Note that, on either definition, it is a mistake both to exceed quality as well as to fall short of it. If you deliver a Rolls-Royce car when the customer wanted a Ford, then either you or the customer is paying too much. And it could be that the Rolls-Royce is too heavy a car for the weak bridge that the customer has to drive over on their way home. This analogy illustrates a key point in real-life project management: if you deliver excess quality, then someone, either the project or the customer, is paying for it. This is not to deny that exceeding the required quality usually leads to much less pain for the project manager than falling short does, and when planning your margin of safety always aim high rather than low in terms of quality. But the point is that you should aim to meet or slightly exceed quality targets in your deliverables and processes, and you ought not to aim to exceed them by a great extent, or you will be wasting resources. As well as quality being too high or too low, it is possible to have excess variation in quality. This need not mean a deliverable swinging between too high and too low a standard of quality; it can be a problem where quality is within what is acceptable, but in a different way each time, confounding customer expectations. People, especially customers, tend to like consistency much more than constant surprise when it comes to management.