Q: How many operators I need to have at the same time when my telephone center receives 10 calls per minute with an average duration of 30 seconds so that the w

Q: How many operators I need to have at the same time when my telephone center receives 10 calls per minute with an average duration of 30 seconds so that the wait time won't be over 5 minutes? A: X, and then the operators will be busy Y% of their time. Especially if Y is low, many callcenter operators will rethink what SLAs they want to give callers. Many call centers optimise for keeping their operators busy aka paying as few operators as possible (and some of them then show their personnel the queue length or average waiting time and expect them to more rapidly kick out callers when that gets too long) For most people, it’s the same with doctor visits. There is no inherent need to have to wait at a dentist, for example, but if dentists plan to have their day filled with paid work, there has to be. They may even schedule their first patient (possibly even the second) at a time before they plan to start working. It’s different for people whose time is worth (much) more than that of the dentist. They (effectively) pay their dentist to wait for them.