The purpose of a job description is to persuade, as well as to qualify and disqualify candidates before you spend time interviewing them. If you’re looking for someone with a degree in economics, then putting that on the job requirements list will disqualify the candidates without the necessary qualification. On the other hand, the right copy and tone can help you stand out to incredibly desirable candidates.
Here’s a sample of job descriptions, ranked from good to bad. Looking through them alongside their scores makes it obvious why some are better than others, and is a good exercise to teach yourself to get better at writing them.