Users often don’t invest enough time into their messages, resulting in incomplete, unprofessional, or otherwise under-whelming greetings. Sure, crafting a greeting doesn’t sound all that complicated; however, there are a number of pitfalls users can fall into—i.e. informality, terseness, sincerity, lack of direction, and more. While none of these sound too catastrophic, they are often interrelated. As such, they tend to worsen any problem. For example, humor can cause informality, worsen ambiguity, and weaken sincerity. That being said, users should strive to avoid ALL these pitfalls.
In certain situations, it’s a good idea to let a call go to voicemail. If you’re in a loud area, unable to spend 10-15 minutes talking, or are otherwise distracted, don’t answer. Recruiters who cold-call candidates will understand that you’re simply unavailable – but make sure to return calls in a timely manner. If possible, call back during regular business hours.

Set the expectation by providing a realistic timeline for when the caller can expect a return call. Remember once the expectation has been made, make sure you follow up and return the call as promised.
37. You have reached [your name] at [your company]. Thank you for calling. Please leave your name, number and a message, and I will get right back to you.