How much time your operation loses on voicemail

August 27, 20263 min read

Each voicemail eats about 18 seconds of an agent before they hang up. With 30 people dialing, that is nearly 40 hours a month talking to machines.

The math

Nearly a full work week of one agent, every month, spent on answering machines. In older lists the voicemail rate goes over 20% and the figure approaches 55 hours.

The cost you do not see

Time is the obvious part. There are two less visible effects:

It inflates your contact rate

If your system counts as "contacted" every call someone picked up, voicemails go into that count. Your report says you talked to more people than you did. We cover it in how to measure the real contact rate.

It wears the agent down

Twelve voicemails a day is twelve times someone gets ready to talk and finds a recording. It shows up in no report, but it shows up in turnover.

Why classic AMD is not enough

The AMD() application in Asterisk decides by measuring the rhythm of the audio: greeting length and silences. It works on the average case and fails at the edges:

• A voicemail starting with "Hello..." passes as a person.
• Someone answering quietly gets cut as voicemail.

The second error is the expensive one: you do not lose time, you lose the contact, and it shows up in the report as voicemail.

The approach that does tell them apart

A recording went through a microphone and a codec before arriving; a live voice did not. That fingerprint stays in the timbre of the audio and cannot be faked by speaking differently. Analyzing it gives a classification with a confidence percentage, instead of a rigid rule that fails at the edges.

NeervoX has that detection built into its dialing, and it also exists as a separate product, NeerBat, if you want to add it to an Asterisk or Vicidial you already run.

Measure your own case first

1. Filter last month's answered calls.
2. Count those that lasted under 25 seconds and were dispositioned as no contact.
3. Multiply by their average duration.

That number, in hours, is what your operation gives away to answering machines.

Frequently asked questions

What percentage of answered calls are voicemail?

Between 10% and 20% in average-quality lists, and over 25% in older lists or lists with outdated data.

How much time is lost on each voicemail?

Between 15 and 20 seconds. The agent greets, waits for a reply, hears the recorded message and only then hangs up.

Is voicemail detection useful if I already run Vicidial?

Yes. It can be added to an existing Asterisk or Vicidial installation without migrating the dialer or modifying the dialplan.