I normally ask at the job interview, if they know an average date, when they will have decided about the job or not. Normally a few days after that I call, and ask friendly about information, if the job is already been given to someone, or if the desiscion is still to do and so on. So I dont bug them, but if you are job seeking its as well for you good to know, which job chances might still exist, and which are definitly already gone.
As well that, when you are unemployed in my country, you can get payment from your unemployment insurance, but therefore you need to proof as well that you are seeking on your own a new job meanwhile. So the jobcenter assistens normally also want to know, about the actual status of your jobsearching.