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.
First-time sales outreach response is plummeting. According to Jill Konrath, 97% of all business calls now go to voicemail.

Most people try to rush and explain everything they do in 15 seconds. This DOESN’T WORK! Not only is this overwhelming, but it’s akin to showing all your cards in a game of poker. Effective voicemails provide a warm introduction, leave enough room for curiosity, and provide a reason your lead should call you back. What is the right voicemail to leave personal representatives/prospective sellers?
You probably touched on this at the end of your last conversation, but if you haven't heard from your prospect in a while, this can be a useful strategy for getting back on their radar.