From VoIP.ms Wiki
If there is a digit that can be pressed, if 'play instructions before beep' is set to 'no', to play those instructions, it would be useful to note that here. [Later in the article it notes 'press 0 (zero) for options' - if that is true for hearing instructions, it would be useful to so note.]
I would guess that the expected use case is to have a caller hear a message, then be sent to voice mail. As I read this article, 'voicemail' sets up voice mail, once reached. No mention of a message is contained in either 'Assigning your Voicemail' sections. If appropriate, could a setup case be described wherein the call (upon no answer, for example) is routed to a phone recording (saying, for example, "Please leave a message after the beep."), which is in turn routed to voice mail. If this is not the correct setup procedure, mentioning the correct procedure would be useful.
- reading further, I now see that the message prompts are recorded via the voice mail system itself. It would be worth noting that earlier in the article, preventing the question above.