The Plan is alive...
It’s almost funny in a tragic sort of way how many project managers seems to think a project plan is a one-time event in the project. It isn’t. It is a continious task through out the project. As the project progresses, a bright project manager ajusts the plan so it fits the actual project progress. If the project plan isn’t updated, there might be selveral reasons. Updating the plan maybe causing a headace and take hours and hours. Keeping the plan up to date must be worth the effort, and if your project planning tool is easy to use and manage, then you just don’t do it.