One of the odd side-effects of keeping your plans up-to-date is the standing wave. In this situation, you always plan to update your plans over the next few weeks. Since projects that are behind schedule tend to get further behind schedule, this "update the plan soon" strategy requires larger and larger resources to be applied over the next few weeks. The wave gets larger and larger with no corrective action taken. Rescheduling and replanning in general require action, not just promises that things will be fixed soon. Just because you are only a few days behind, don't put off updating the plan. All projects fall behind one day at a time.
Reference:
Brooks, F., The Mythical Man-Month, Reading, MA: Addison-Wesley, 1975.
