Retraining is important for employees to keep their skills updated as work environments and technologies change over time. The document outlines the need for retraining due to factors like mechanization, inefficiencies, and technological developments. It then describes the process of retraining which involves identifying needed changes, setting objectives, and choosing retraining methods. Common retraining methods include on-the-job and off-the-job approaches. The benefits of retraining are also highlighted.