Integrated Project Management

Additional Sources of Project Overrun

Critical path tasks that overrun their most-of-the-time estimates cause project time overruns. Tasks that are not on the critical path can overrun their most-of-the-time estimates without affecting a project's time if the overrun is less than the slack between this noncritical path task and its critical path successor. However, if a noncritical path task overruns by an amount greater than its slack, it can cause a project time overrun (that is, if a task Δ is greater than the slack between it and the following critical path task, it can cause trouble).

So far we have only considered project time overruns caused by the time overruns of critical path tasks. Noncritical path tasks can cause just as much over-run ...