The project schedule plan is most likely the most visible plan to project leaders, team members, and stakeholders. This is part of the reason why blog post author Marian Haus, PMP, sees it as one of the most important project management assets a project manager needs to control.
Haus explains how project sponsors want to see the schedule to know if things are on time. Those who will benefit from the project want to know where you are currently, and your team will need it to schedule work and expectations. All of this is dependent on the document being correct:
Now, if your project schedule is incomplete or flawed—for example, it's missing work tasks or it features wrong dependencies between project tasks—you will most likely steer your project into a wall. And even if you put everything right into it (i.e., all work activities, the right durations, right resources assigned, right dependencies), that still might not be sufficient for a successful delivery. That's because, as you know, a project schedule is not a linear sequencing of work tasks that perform exactly as initially planned.
Haus suggests a few techniques to help with keeping the project schedule plan up to date and responsive, including resource leveling, schedule crashing, and fast-tracking.
Read the full post here: http://blogs.pmi.org/blog/voices_on_project_management/2014/02/keep-the-schedule-plan-strong.html