The Critical PathMuhammad Zeeshan Ali, PMP, PMI-ACP
“Why so Critical?”
During the early part of my career, I still remember facing one question very frequently during the interviews: “What is a Critical Path?”. Generally the response used to be that Critical Path is the shortest time to complete the project. The discussion never went beyond the basic definition of Critical Path.
In reality, the importance of Critical Path is much more than just a definition. For a seasoned Project Manager, it is an important piece of tool/item therefore its in-depth understanding and proper handling is important for the project. In simplest words, the Critical Path cannot afford any delays. Any activity on the Critical Path suffering a delay will cause project delay of at least the same magnitude.
The general mistake Project Managers make is to plan all tasks or major portions of the schedule on Critical path. This is generally to cater the pressure of keeping the timeline to the minimal. In reality this means that they are planning the project with the highest risk level of affecting the schedule delay since there is never much/any breathing space available to the project as project reserve.
The question is why is it so that almost every other activity is planned on Critical Path? The main reason is that mostly when the Project Manager creates a schedule, he/she doesn’t have the liberty to add much reserve time. The customer mostly has this mindset that such reserves will be an “intentional delay” and it is common for them to emphasize on removing that reserve.
The Senior Management is also never too comfortable in having these reserves in the Project Schedule. They believe that having such reserve reflects that the project team will definitely work with low velocity and will be expected to require additional time to remove bugs or any other rework .The other reason for Senior Management is that adding reserves do increase the upfront cost of the project and this, especially in competitive bidding, can be a problem in winning the project.
Some Project Managers, in order to avoid resistance from the customer or management team, simply add the reserve to some other task effort rather than adding a specific reserve in the Project Schedule. The biggest issue with adding additional time to other tasks is the theory that resources will take as much time as allocated to a task. This means that resources will take all other time (original task effort + additional project reserve) but will only complete the respective task and that way the reserve will be wasted. Otherwise the task might have ended early but since, as per project schedule, they have margin to slow down so they will use that advantage there and then.
The Critical Path needs full respect and the Project Managers should always add proper Project Reserve. The stakeholders might not be comfortable most of the time but it is the job of the Project Manager to defend it. As I have discussed in my other article “At what stage the Projects fail?”, that the planning part is the most important phase in any project. The stakeholders should either accept the estimates including the reserves or they should agree to bear the consequences related to the risks involved as a result of planning with reserves. The Critical Path will always remain critical to the Project Schedule.