An instructional manual is necessary for clarity, consistency, efficiency, safety, troubleshooting, and legal compliance. It provides clear and detailed guidance, ensuring users understand how to use a product or perform a task correctly. Following a standardized format and language maintains consistency across different users. The manual enhances efficiency by enabling quick reference, offers troubleshooting tips, promotes safety through guidelines, and helps meet legal requirements. Overall, it is a valuable resource, ensuring a positive user experience.