We all have experiences of having to stop working on one task so that progress can be accomplished on another task in another project. Often, we wonder if all this jumping around makes sense because it comes with the penalties of reduced focus and loss of efficiency. However, there is a reason for this multi-tasking environment. Project managers are responsible to a customer for successful completion of a project. These customers can be internal or external to an organization.
Customers have a tendency to be demanding.
They think that their project is the highest priority and they want to see frequent progress on their project. Resources tend to migrate between projects in response to the latest, loudest customer demand in an attempt to keep as many customers satisfied as possible. This focus on showing progress on as many active projects as possible is the major cause of multi-tasking. As we will see, this focus is to the detriment of the overall project thru-put of the organization. Assume we have four projects, A, B, C, and D each of which is estimated to take four weeks to complete.