Estimates, Targets, and Commitments
When executives ask for an “estimate,” they’re often asking for a commitment or for a plan to meet a target. The distinctions between estimates, targets, and commitments are critical to understanding what an estimate is, what an estimate is not, and how to make your estimates better.
What you need to do is to distinguish between estimates, targets, and commitments.
An estimate is a prediction of how long a project will take or how much it will cost. But estimation on software projects interplays with business targets, commitments, and control.
A target is a statement of a desirable business objective. Businesses have important reasons to establish targets independent of software estimates. But the fact that a target is desirable or even mandatory does not necessarily mean that it is achievable.
A commitment is a promise to deliver defined functionality at a specific level of quality by a certain date. A commitment can be the same as the estimate, or it can be more aggressive or more conservative than the estimate. In other words, do not assume that the commitment has to be the same as the estimate; it doesn’t.