Dr. Simon mentioned the Work Breakdown Structure in Planning Phase. So what is the importance of WBS in project management life cycle, how is it helpful?

According me this WBS makes the work more efficient for planning purpose, as in this the work is assigned the time frames and costs that gives a better clear view of the project. It helps to reduce complications of number of tasks done together. Because of this structure it would be of great help for any project manager to oversee the task more efficiently. It specially defines each work element and ways that helps to organise the work space.