Nobody is perfertto, and therefore it happens that something escapes in the analysis phase and then inevitably you have to manage the addition in the development phase.
Prince2 frames these analysis gaps in the term “off-specification”.
The PMI instead places these situations in two different processes depending on the impact of the request.
If the request is manageable within the agreed tolerance limits, a corrective action is sufficient, if the request has such an impact that it exceeds these limits, then it is necessary to follow the change management process.
The theory would have it that these cases were only exceptions because, if we have created a complete list of stakeholders and we have created the work breakdown structure, the risk of forgetting some specifics should be minimal.
The theory, however, also provides for the fact that the Project Manager is human and therefore finds himself from time to time to manage these situations.
The first step that the Project Manager must take in this case, after making sure he has understood the request, is to evaluate together with the team what impacts the addition of the specification could have on time, costs, risks, and quality.
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