Story EstimationMuhammad Zeeshan Ali, PMP, PMI-ACP
The core essence of Project Management and preparing a Project Schedule is the effort estimates provided by the resources. May it be the traditional waterfall model or any of the Agile methodologies, the aim is always providing good estimates. The good estimates don’t necessarily mean estimates with early delivery, rather it means that at the end the actual effort is closest to the estimates. The good estimates are based on ground realities and are provided taking into account most of the possible risks.
Story estimation not only provides an opportunity for all the stakeholders to set realistic expectations regarding the work but also helps the Project Manager to make timely decisions if anything goes off-track as per plan.
One issue that I have mostly experienced regarding estimation is that the estimates, provided by the resources, vary from actual work because of two main reasons; first one is that resources over-estimate to be on the safer side. General perspective is that it is better to give double or even more rather than the actual effort as it will be easier to achieve that target. If the work is completed earlier, then it will be considered as an achievement. Second reason for variance in estimates is that the resources generally do not consider the whole scope of the work or the different roles that will be required to complete the task. In both cases, the Project has to suffer.
As a Project Manager, I always prefer working on Agile estimates because they seem to be more realistic and practical solutions. Since the User Stories, in Agile, are more broken-down as compared to the waterfall model and being more close to the actual work therefore they are more effective. The other important factor in getting good estimates, in Agile, is the ability to define “Acceptance Criteria” easily so that helps in better understanding of expectations and Scope of Work. Since Agile has small iterations thus the risk levels, for most of the activities, are at lower end as a result there is less amount of rework.
Another good strategy to have better estimates is to involve all the relevant stakeholders and team members in the estimation exercise. This helps the team to agree on better story points and also covers all the dimensions that may involve in the completion of the story.
Another important thing is to give proper time to the estimation phase and have proper process and framework for that just like any other activity on the project . Despite all having agreement regarding the importance of this phase but ironically it is executed very haphazardly. The other thing is that at the time of the Sales process, the people who work on the bidding are totally different from the actual team who will work on the project. This is one of the main reasons why we often see causing quite a variation in the project estimates and actual work.