Estimating Project Completion

Micro Learning Unit

One of the most common questions asked by the client and other stakeholders is “When will the project be completed?”
They all want to hear the same confident answer: “On time and according to plan.”
It is a project manager’s job to do everything possible to fulfill this expectation. At the same time, the project manager should avoid buckling under the pressure of this expectation and embellishing the truth.
The project manager’s task is to provide a realistic estimation for the work remaining until project completion and offer alternatives to reduce the risk of failing to meet the projected finish date.

The projected finish date of the project should be determinable at any given point as long as the work plan is managed on an ongoing and detailed basis, reflecting the actual progress of the project.

Controlling the progress of the entire project begins with controlling the tasks detailed in the work plan. Nevertheless, it is impossible to deduce the condition of the entire project just by looking at the progress of the tasks. While it is true that evaluating the progress of the work does indicate the scope of the work already completed, it does not provide an accurate picture of the scope of the work remaining.

In order to obtain a more accurate picture regarding the expected finish date of the project, not only must the scope of work already completed be updated at each stage, but also and especially the estimate of the work remaining.

Updating the duration of the project following current estimates of task completion is typically based on one of two assumptions:

What was will continue to be

History will repeat itself

What was will continue to be

For example, if there has been an average slide of about 20% beyond the original estimate of task duration, it is likely that there will continue to be such a slide for the rest of the project, too; the project estimates should be updated accordingly.

What was will not continue to be

History will not repeat itself

What was will not continue to be

The past causes of timing deviations are not likely to repeat themselves. Therefore, there is no reason to update the plan based on past results. Rather, work should be resumed at the originally planned pace.

Ensuring the most accurate estimate for the completion of the project relies on several elements: ongoing updates of remaining work (rather than work already completed); evaluation of task duration estimates, task constraints and task connections; and updates of the foregoing as needed.

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