Project schedule is a required tool of project management but unfortunately experience tell us that projects often, even usually, overrun their schedules thus their budgets.
Why often are the project schedule not reliable?
The discussion is opened, and as a quick answer we could highlight the following weaknesses of Project Schedules:
- Knowledge of the discipline and expertise of the person in charge of the planning
- Poor scheduling practice
- Unrealistic deadlines
- Uncertainty in activity durations
Those would result in the non-reliable project schedule, and if it is not, the project team will often not use it for the execution as it will not be enough robust. It will become a nice wall paper and that’s it.
The project scheduler will have difficulty to collect the progress to update the schedule and will be demotivated.
An integrated project schedule is a fundamental management tool and the project scheduler will have the knowledge of the details of the project, often more than the project manager. Often insufficient experienced schedulers are assigned, and project schedules are developed by inexpert schedulers. So don’t be surprised if the project schedules developed is not in the highest quality.
What are the benefits from a reliable project schedule?
The project schedule is not only the roadmap of the execution it is also a tool for decision making. It will be used for cost estimation, risk analysis, cost and time contingencies estimation, simulation and optimization of the resource usage… If the project schedule is not robust and reliable then it will not be used as it could be.
Here are listed some benefits from a reliable schedule:
- Helps to analyze how change affects the execution
- Allows to do what-if scenario to analyze and understand the cost impact if the project doesn’t finish on time.
- Developing a time-phased budget baseline (cash flow)
- A schedule risk analysis performed on a well-constructed schedule will show the cost effects of schedule slippages, and define a contingency plan to mitigate risks
- Promote accountability at all level of the project
- Credibility of the forecasted dates (will impact the communication)
- Schedule variance will have an impact on the cost variance due to direct cost (labor, rented equipment, facilities…)
- Help to analyze progress and setup warnings on over target budget or schedule.
How to develop a reliable schedule?
The first step, after assigning an experienced project scheduler, will be to develop the schedule with the respect of the best practices, standards, procedures and other guidelines:
- Scope of work: define the Work Breakdown Structure and the Work Packages, the WBS dictionary should be created and documented
- All activities as defined in the WBS
- Sequences of activities: define the interdependence
- Durations estimation: parametric estimating and schedule uncertainty
- Resources Loading
- The second step will be, once the schedule has been developed, to do a checkup. The following actions should be performed
- Confirm the valid Critical Path (or more than one if applicable)
- Schedule Check (DCMA-14…)
- Schedule Risk Analysis using as inputs the contents of the Risk Register.
- With the result it will be possible to define
- The robustness and flexibility
- The cost and time contingencies
And the last step, but not least, as the schedule is not a wall paper but a live document, it will evolve during the project live-cycle it is important to measure the progress and update the schedule with actuals, changes… and communicate the progress and other performance indexes.
The project scheduler will make sure that
The Project Baseline is maintained
The schedule is updated, look ahead schedule and performance indexes communicated
The schedule narrative is up-to-date.
Changes included, recovery plans, what-if scenario and new schedule risk analysis performed if needed.
Do you think your project schedules are reliable?