If you have not yet done so, please read 6 Reasons Critical Path Schedules Fail – Part 1 Having done CPM scheduling work on hundreds of projects with many different owners and contractors, I have witnessed many bad scheduling practices. We can divide these into two groups, insofar as they pertain (a) to the creation of the initial baseline and (b) to the maintenance of the schedule as the project unfolds. Here are three of the worst practices I have seen when it comes to creating a baseline schedule:
A good schedule needs to have collaborative input from all parties directly involved in the project, so that everyone can sign on to support the same plan. When this is not done, competing project visions can emerge, creating tension and conflict between contractors, subs, and owners. Perhaps the most egregious example of this I have witnessed involved a large school project in which the general contractor refused to coordinate with his subs and develop a detailed baseline schedule, preferring to manage by the seat of his pants. As might be expected, several of the subs had problems coordinating their work because they had no detailed overall plan telling them in advance when and where they needed to be working. This eventually resulted in massive delays and damage claims by the subs against the general contractor.
The logic in a CPM schedule should reflect the real dependencies of tasks and/or resources. Frequently I see schedules in which activities have been tied together even though they are not actually related just because one is planned to occur after the other. For example, I have seen schedules where exterior landscaping work was tied to interior insulation and drywall for the sole reason of tying landscaping to an activity that would push it out to a certain point in the schedule. One problem with this kind of logic is that it can seriously distort the critical path, undermining the value of the CPM as a management and delay analysis tool. Another problem is that it masks inefficiencies in a project that, if not made explicit by identifying real dependencies, could cost unnecessary considerable time and money.
I have worked with many contractors who see the baseline schedule as nothing more than a contract requirement to fulfill. Accordingly, they only put enough detail and thought into the CPM to satisfy the owner or contract manager. Consequently, unless the owner or construction manager closely reviews the schedule, the schedule tends to be poorly organized, insufficiently detailed, and inaccurate, as little concern is taken to make sure the durations and logic are sound and accurately reflect the job plan. Of course, if that is how the schedule is treated, then it will be good for nothing but satisfying a contract requirement. But that is to neglect the single most useful project management tool—the CPM schedule. The well-designed schedule provides a clear road map for the project, reflects the collaborative support of all involved, makes it possible to precisely monitor progress by comparison with the baseline, and facilitates efficient completion and recovery from delays.