At its core, sales is a people-oriented practice — so naturally, if you want to leave an effective sales voicemail, you need to sound like a person. If you sound too rigid or robotic, your message might come off as imposing or impersonal.
Updating the voicemail message with your own greeting allows you to let callers know they’ve reached the correct person; the process is fast and easy. How to Change the Outgoing Voicemail Message on IPhone (iOS 9 or later) Tap the phone icon (the same one you use to make a call).

It is no surprise that your actual voice mail greeting must be delivered in the same way: Professional, clear, brief, and to the point. In a previous blog, "Marketing Messages on Your Cell Say You Mean Business," some techniques for making a professional voice mail greeting were discussed. There are many similarities between leaving a voice mail, and producing a voice mail greeting. You want your callers and receivers to hear a confident and professional person on the other end delivering a coherent message. You should introduce yourself to a prospective client in a personal way. An email doesn't generate much discussion, nor does it necessarily show you went the extra mile in contacting the client. Generating conversation. A professional, well conveyed voice message shows the voice mail receiver that you are confident and well-spoken, and that there is a person behind the message. Emails can be prepared, edited, and revised unlike voice mail messages An email or email chain thread is documentation of a conversation that can easily be referenced In an email you can include a phone number, address, website, etc that may be hard to remember or record through voice mail communication Emails can be forwarded, CC'ed, and blasted.
Leaving ambiguous voicemail messages almost guarantees that you will not get all you could have from the conversation, as you did not give the person you called the opportunity to prepare for your call.