A commonly overlooked aspect of voicemail etiquette is your own mailbox greeting. A lot of us simply set it and forget it when we first get our phones, which for some of us was when we were teens, or we don’t have anything set up at all.
Creating a professional voicemail greeting isn’t complicated, but you need to keep a few things in mind to ensure success. The following tips will help: Be friendly and welcoming - let your company's personality shine!; Have a clear voice, speak at a slow to moderate pace, minimize background noise; Ensure the greeting is human and approachable; Keep the greeting short and informative; Ensure the greeting doesn’t sound robotic or unnatural; Show your gratitude for the call by saying thank you; Manage expectations by clearly stating when the client can expect a callback.

Most cell phones show the number and voicemail duration when a call is missed. So if the recipient sees the message is from an unknown number and only a few seconds long, they'll assume it's not important and hit delete. Since the message doesn't appear to be substantive, they're not prompted to listen.
You have reached xxx-xxxx. We picked this machine up at a garage sale in “as-is” condition. You can try to leave a message on it, but we are not sure it will be recorded. If we don’t return your call, it means the machine did not work.