The initial project timeline is never set. The planning process of a project breaks down the project into actionable tasks (WBS), allowing team to make rough estimates for each task, but the timeline will constantly be revisited. When a team is put together and a Team Communication Plan is completed, PM will have several team meetings where the project breakdown, tasks, and the duration of each task can be discussed. This time duration is estimated by using past experience, project deadlines, and the project’s critical path. However, due to the nature of a project, especially complex projects with thousands of tasks, the timeline will likely run through several iterations in accordance to the progress of the project. If task deadlines are missed, the schedule timeline is pushed back and the PM must ensure the schedule does not get pushed beyond the project’s late finish time.