According to Torrington, a job description is usually developed by conducting a job analysis, which includes examining the tasks and sequences of tasks necessary to perform the job. The analysis considers the areas of knowledge and skills needed for the job. A job usually includes several roles. According to Hall, the job description might be broadened to form a person specification or may be known as "terms of reference". The person/job specification can be presented as a stand-alone document, but in practice it is usually included within the job description. A job description is often used by employers in the recruitment process.
The process of developing job descriptions often sheds light on the nature of a job as well as suggests that there are alternative methods of performing essential job tasks. Job analysis may help encourage management and staff to work together in identifying and streamlining the essential and marginal job functions.
Additionally, job descriptions are handy for both employees and managers: after hiring, both can refer back to the responsibilities and other information to gauge how well they’re doing their job and whether they’re matching expectations.
Properly written job position descriptions are often the only document that totally define what a role is, what skills are required to perform it, and where the role fits in an organization. This makes it simple to identify candidates that are a good fit for the role and also to hold candidates accountable if they are not performing essential duties that are required in the role.