Formalized PerformanceManagement is making a comeback in organizations under financial stress (who isn't?). Done properly, the process is intended to promote uniformity across operating units and therefore promote fairness, help to stretch capabilities of the units being managed, and provide a bidirectional feedback mechanism so management and staff can work well together.
Done properly[...]. There are many reasons for doing PerformanceManagement properly, the above are just some of them. YMMV