You just need to know a few small facts about voicemail calling patterns and the whole thing becomes crystal clear (these statistics are taken from actual usage in the last few months):
- average deposit duration: 19 seconds
- average retrieval duration: 58 seconds
- ratio of retrievals to deposits: 3 to 1
They want to be able to offer free* voicemail deposits. Because voicemail deposits are so short, this really doesn’t cost much anyway, even if you’re an MVNO without your own voicemail platform. So it’s not hard to cross-subsidize.
All you do is load up the price on the retrieval. Because of 30-second blocking, and because the average retrieval call picks up more than one message, they are likely to be more than 30-seconds, and with short calls like this, the margin boost is higher than ever. So just the voicemail exercise is at worst revenue neutral, but probably a winner.
Of course the icing on the cake is slipping in that little increase in connection fees. Carriers, service providers, and MVNOs just love connection fees. They are the best contributors to gross margin in the industry. Every now and then, Telstra shifts them up just slightly. And very few customers have not taken a service based on flagfall. So the industry is happy for it to remain our own little secret!