A good job description gives members of your team a very precise idea of what you expect from them, including making the real meaning of the job clear.
Much like an organization's vision statement Add to My Personal Learning Plan, a well-written job description expresses the role in terms of its overall purpose. Articulated this way, it is a meaningful framework for managing performance expectations, evaluating people, and giving feedback.
Much more than a simple list of duties, it's a dynamic document that identifies key areas of responsibility, and the associated critical success factors Add to My Personal Learning Plan of a position.
For example, Sally, the receptionist, may answer the phones every day but describing her job as a "phone answerer" in no way reflects the real purpose of her role. It doesn't tell Sally what is expected of her, or why her position is of value to the company. What if an automatic phone system is installed and she no longer has to physically answer calls? How do you describe her position then?
Answering the phone is only one duty; her larger role is to be the primary contact for customers. Using a vision statement approach you might say that "the receptionist's job is to welcome people to the facility and convey a family atmosphere from first contact". This is much more informative and humane, and much more likely to motivate the full set of behaviors that you want. By thinking first about why you have a receptionist, and then working back to list the duties related to that – you'll have a stronger and more meaningful description of the job function.
Do your company's job descriptions focus on individual tasks or on overall roles and functions? It's important to write job descriptions that are relevant and that include the major functions and purpose of each position. If done well, the job description will answer these questions: "Why is this job important?"; "What are my key responsibilities and priorities?"; and "What are my critical success factors?"https://www.mindtools.com/pages/article/newTMM_64.htm