Refining estimates may be necessary for a number of reasons. for example, a manager getting further into a project and obtaining a better understanding of what needs to be done to accomplish a project

Refining estimates may be necessary for a number of reasons. for example, a manager getting further into a project and obtaining a better understanding of what needs to be done to accomplish a project and meet the needs of the customer is an example of hidden interaction costs. changes in project scope. things going wrong on a project. normal conditions not applying. there is never a good reason to refine estimates.