Why You Should Educate Management on Estimating Activity Durations

Project Manager frustrated by mandated project duration. “The bearing of a child takes nine months no matter how many women are assigned” (Brooks, 1975, p.17). Similarly, in project delivery, there are some activities that take the time that they take, no matter how aggressively estimated or how many staff are assigned.

Yet so often we estimate activity durations based on throwing additional resources at the delivery process, as though this would shorten timelines and meet the unrealistic expectations of senior management or our clients for how long the project should take. As project management professionals, we need to wrestle control back to those of us who are in the trenches and who can provide realistic project timelines.

Recalling past blogs to get to this point in the 52 Project Management Success Tips, I’ve discussed the application of the people aspects of project delivery in the following articles:

In discussing this next topic in the planning process group – estimating activity durations – I am reminded of what the “PMBOK® Guide” said about estimating (in this case, regarding analogous estimating): “When estimating durations, this technique relies on the actual duration of previous, similar projects as the duration of the current project.” (Project Management Institute, 2017, p.200). The Guide goes on to describe several methods to estimate activity duration, and most (if not all) reference the use of historical data.

It all sounds so logical, doesn’t it? Define the project activities. Sequence them logically. Estimate the activity durations. And successful delivery will follow.

But let me share my experience.

As a consultant, almost all of my work over the life of my career was derived based on winning competitive procurements. The organizations to which we submitted our proposals would typically dictate their project durations in the procurement requirements. Sometimes they would even dictate the durations for each project phase.

We seldom had the luxury of proposing activity durations to derive a more feasible project duration than the one that was dictated. In preparing our proposals, we would first have to determine whether we could meet the client’s mandated timeframe, and then estimate the activity durations to back into that timeframe. In many cases, if we wanted the work, we would have to bid to the mandated duration or forfeit the job.

I assume this is no different for an internal IT organization responding to senior management’s request for an estimate for a new project. The IT manager knows her staff availability and skill sets, but still finds herself fitting her estimates to management’s decree of how long the project should take.

Do you see where I’m going with this?

Is it any wonder that so many projects are delivered over budget, or come in late, or fail altogether?

As long as we have legislators and government organizations whose new regulations must be supported by computer systems, or corporate executives that require new systems for competitive advantage – and these systems are required by a date certain – we will feel obligated to estimate activity durations that match their expectations.

Yes, it’s our job as project management professionals to deliver to our clients’ expectations. But it is also our job to educate those who are setting the expectations as to what is optimum for successful project delivery. Over time we – the professionals – must become the major influencers of how project duration is estimated, and thereby guarantee a higher probability of project delivery success. This would bring more credibility for our industry as a whole.

But I digress. Forgive me for my momentary lapse into Utopia (though I strongly believe that this is possible). Over the course of my career, I have had the privilege of working with many experienced estimating teams. I was able to learn and apply several techniques for estimating activity durations (and by extrapolation, project duration). In many cases, these estimating techniques not only assisted our team in developing solid estimates for the project duration and project resources, but also assisted us in educating client management as to what it really would take to deliver their projects.

Sometimes we had the opportunity to influence the clients’ expectations prior to submitting our final proposals. Sometimes we had to win the bid first, and subsequently work with the client on how best to meet their expectations.

Regardless of the specific estimating techniques used, however, the most effective method for developing our activity duration and resource estimates was in group decision-making. We involved delivery staff who were expert in the technical execution of our projects to help develop solid estimates.

The give-and-take between the initial project estimators charged with selling the project, and the delivery staff who would be tasked with delivery it, was invaluable. While those tasked with delivery brought realistic experience to the estimating process, those tasked with the sale challenged them to be more aggressive in their estimates by appealing to their creativity. Career opportunities would open up for those who helped win the projects using creative and aggressively doable solutions.

The planning process is as critical to the overall success of the project as is the actual delivery. Planning requires concerted effort, a repository of solid metrics, expert judgment, and a combination of both sales and delivery perspectives to estimate well.

Now back to my soapbox and vision of project management Utopia

When we as project delivery experts begin to educate our senior management and our clients to base their expectations on our estimating experience rather than their wishful thinking, we will have a far greater chance of project delivery success. Then, and only then, will our industry attain the credibility it deserves in its ability to deliver. Our senior management and our clients will benefit because they will have more successful projects. Our project staff will benefit because we will have taken the people aspects of project management into consideration, and pave the way for a greater opportunity to succeed.

Let me paraphrase the Brooks quote introduced at the beginning of this article: just because one woman can deliver a baby in nine months, doesn’t mean that nine women can deliver that same baby in one month. We need to demand that the estimating of activity and project duration be left in the hands of the project delivery experts.


Brooks, Frederick P., Jr. The Mythical Man-month: Essays on Software Engineering. 1975. Reading, MA: Addison-Wesley Publishing Company, Inc., 1982, Print.

Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Sixth Edition. Newton Square, PA: PMI Publications, 2017, Print.

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