Project success is, among other things, very much dependent on all the team members knowing what to do. Since it is not possible for the project manager to be constantly holding her team members hands the best way to keep the team members informed about what needs to be done is an up-to-date plan. The project plan, not to be confused with the project schedule, is a great vehicle to convey to the team members and other stakeholders the intended output of the project, what needs to be done, how and when.
All too often have we seen that the project plan gets a lot of attention at the start of the project and then gets forgotten. Keeping the project plan up-to-date has multiple benefits.
First of all it forces you as the project manager to review the currency of the plan and in particular the business case.
Secondly it ensures that the team members have a way of knowing how the project is run and what needs to be done.
Having an up-to-date project plan is one of many concurrent means, you as a project manager need to employ, to keep your team and other stakeholders informed. Finally we like to suggest to review the plan on a regular basis with your teamleads and key team members.
This lesson learned is also related to the plans are like food lesson learned.