Time estimation in project management

We have discussed last week the importance of the project scope that defines the requirements and users’ expectations from the project. Based on this scope, the Project Manager or PMO start the requirements analysis and estimations that is also a crucial phase of the project due to the simple fact that cost and time estimations are an important for decision makers and they base their judgments in general on these lasts (Kerzner, 2009).
Each time, when it is question of estimation, many random facts might occur, and the uncertainty is inevitable. Time estimations as costs’ are not an exact science which mean that it can be based on suggestions and estimations and not facts; for this reason, time miss-estimation is also one of the reasons of projects failing, as stated by Schwalbe “Many IT projects are failures in terms of meeting scope, time and costs. PM a often cite delivering projects on time, which is one of their biggest challenges and main cause of conflict” (Schwalbe, 2011).

Due to these reasons a set of methods and technics have been developed to help project managers for the estimations. The set of technics and tools is known as the Project Time Management, which is, involves six processes:
1. Defining the activities: In this phase the project is divided into smaller tasks that should be performed by the different project’s members. This is generally based on the WBS to determine the different work elements, it generates in final, a list of tasks.
2. Sequencing activities: Here the aim is to define the relationship between the different tasks and define what is called the project schedule network diagram.
3. Resources estimation: During this phase, the project manager tries to determine for each tasks, the resources required (human or non-human). This phase is important as it generates the activity resources requirements and the resources breakdown structure.
4. Activities duration’s estimations: In this phase, a further analyze of the tasks is undertaken to determine how many work hours/days/resources are needed for each task. At the end of this step the activity duration estimations are generated.
5. Developing the schedule: This phase consist in the general analysis of all the outputs of previous tasks to create the global project schedule including baselines and schedule data.
6. Controlling the schedule: This step consist in the definition of methods and technics to control the respect of project schedule as the work performance measurements, organizational process assets and change request (Schwalbe,2011).

If we review the different processes of the Project Time Management we can notice that they are closely related and the outputs of each steps are used as inputs in the next one. Defining the activities is the most important in which the project is divided into small tasks which can easily be estimated and later assigned to resources. In order to provide good time estimation, the project manager should be aware of the teams skills and also the project’s scope should be clear enough, it was really recommended to involve technical teams in the time estimations as they are the best person who know how long a specific task might take (Jones,2007).

References:

– Kathy Schwalbe (2011). Information technology, Project Management. ISBN: 978-1-111-22175-1.
– Richard Jones (2007). Project Management Survival: A Practical Guide to Leading, Managing and delivering challenging projects. ISBN: 978-0-7494-5010-6.
– Harold Kerzner (2009). Project Management: A Systems Approach to Planning, Scheduling, and Controlling. ISBN: 978-0-470-27870-3.