Job Instruction is a systematic training method used to ensure employees can perform job tasks correctly, safely, and consistently. It aims to develop a well-trained workforce through reducing mistakes, accidents, equipment damage, and customer complaints. The advantages of Job Instruction include promoting safety, increasing productivity, maintaining best practices, and reducing costs compared to other training methods. While it has some disadvantages like training costs and potential reductions in team productivity, Job Instruction overall provides a simple and effective way to train employees on proper job procedures and techniques.