Should your resume include a description of your regular duties and responsibilities? For example, if you're a store manager do you need to say that you perform opening and closing procedures, supervise staff, resolve customer concerns, manage cash and receipts, hire and train employees, conduct performance evaluations, etc.?
Probably not, but it does depend on your job target.
The rule of thumb is this: If the person you expect to read your resume will already have a basic understanding of what someone in your position does on a daily basis, there is no need to waste their time by listing it all on your resume - there are more important things to include. However, if you think the reader may not know what someone in your position actually does, then a description of your duties and responsibilities is important to include.
So how do you know what the reader will know? You make an educated guess and usually it comes down to your job target. If you're continuing along the same path in the same industry, chances are the reader will have a basic understanding of what you do. If you're heading off in a new direction in a different industry, you may want to dedicate some space on your resume to educate the reader.
For example, if you're a store manager and you're applying for a new job as a store manager - or even a district manager or other position in retail management - in all likelihood you'll be applying to a company recruiter, third-party recruiter, HR manager, or district or regional manager (depending on the position you're applying for). All of those people will already know what a typical store manager does, even if they have never worked for your company before. Listing all the things a store manager does on a regular basis will be a waste of time.
If you're applying for a management position in a completely different field, they may not know all the different things a store manager does. In that case, it can be helpful to briefly describe what you do (don't copy your job description) before getting into your achievements. However, remember that many duties can and should be phrased as an achievement. "Hired and trained 10 new sales associates" is much more informative to the reader than "Responsible for hiring and training."
It's always important to put yourself in the employer's shoes when job searching, and that includes writing your resume. After all, communication between two parties is always enhanced when each person tries to see things from the other's perspective.