Article Written by Gwen Miller, PMP, APMC, CSM 

A major task for a project manager, and/or the project team, is to estimate the work effort needed to deliver the project.  Does this task seem to be one of the hardest to ‘get right?’..Do we give the impression that the project estimates are actual commitments?  Why the confusion? 

What Is An Estimate? 

Loosely defined an estimate is to calculate something approximately or form an approximate judgment or opinion regarding the size of something.  So in essence, when you have completed your work breakdown structure and are satisfied that you have detailed all the tasks for your project, the next step will be to attach a work effort estimate to each task.  Added together, these estimates will determine approximately how long the project will take to complete. 

This level of effort estimate will be your opinion or your project team’s opinion based either on recent past or historical information.  Sometimes it will just be ‘a best guess’ since no one on the team has done anything like it in the past.  And this can cause issues that we may not even recognize since we have been doing it this way forever.  We need to emphasize that we don’t know what we don’t know.  We think it might be but we are not sure.

And the Crystal Ball Says 

Estimating is a key component in project planning.  Many critical elements, such as budget and schedule, are secured based on these estimates.  And once we provide this information to the stakeholder and executive, those estimates magically evolve into commitments.  Why does that happen?  Do they really believe that part of a project manager’s skill set is reliably predicting the future?  Why are we letting ourselves be set up for failure?  Could this be one of the leading factors in determining why we are only successful 38% of the time in successfully delivering a project as documented in the 2010 Standish Chaos Report.

Accurate Estimates – An Oxymoron 

After all, accurate is, by definition, free from error or defect; precise, exact.   

In my opinion, I think others in the organization believe project managers should have all the answers because they have had exposure to many and varied project initiatives.  It also raises the question as to why executives would think that estimates would be accurate. 

Accurate estimates only occur once that task is complete and we know exactly how long it took to complete.  Estimates are not free from error as we all know.  We usually add or subtract an agreed upon percentage of error to justify variances in the estimates.  There is no precision attached to estimates.

A Teachable Moment 

Once we have achieved buy in about what estimates represent (an opinion, judgment or best guess about the time associated with completing a project task), we will have the target delivery date and budget.  Now we need to educate the project team, project sponsors, stakeholders and company leadership that all things being equal, there is a good chance we will make those dates and dollars.  

Most likely there will be some variation.  Knowing that your team, sponsors,  and company leaders understand the concept of estimates, realize that there is a 5, 10 or 15% +/- probability of error in the estimates (those % will be agreed upon before the project is started).  That will be validated once the actual work effort is completed and can be used in estimating in the future.

And Now 

Project Managers will be able to provide estimates without them becoming a commitment.  The project manager will still make every effort to work within the estimates derived during planning.  When an issue or risk does rear its ugly head and affect the project, you will be able to replan and re-estimate remaining tasks and provide the updated information on budget and timeline knowing those involved with the project and the company’s leaders, understand that this is part of project management and the challenges in estimating. 

Do your leaders commit the project to the estimates as if they were exact?  Can they be educated and open to understanding the challenges faced by Project Managers? 

© 2011 Gwen Miller.  All Rights Reserved. 

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