I once blogged about the different types of voicemail message. But every voicemail message is essentially the same thing: a chunk of information conveyed in a way that might be convenient or fun for the person communicating that information, but substantially less convenient for the person receiving it. In that sense, they’re a lot like videocasts.
Let’s think about the reasons why someone might not answer their mobile phone.
They can’t get to their phone in time
You wouldn't believe how many phones are configured so they only ring for a stupidly short time before voicemail kicks in. (My old phone used to ring for fifteen seconds, and that was after I got the nice man in the phone shop to extend it from five seconds.) With the best will in the world, some people are just not going to get to their phone in time if it's upstairs and they're downstairs, or if it's at the bottom of a bag.
Why you shouldn’t leave a voicemail: They’ve just sprinted to the phone, missed your call by seconds and immediately started trying to ring you back. But they can’t get through to you because you’re leaving a voicemail, which they will feel obliged to listen to, further delaying the moment when you actually get to speak to each other.
They're in a meeting, or a swimming pool, or a library, with their phone switched off/on silent
They can read a text much more quickly than they can listen to a voicemail. They can also read a text much more surreptitiously than they can listen to a voicemail.
They're somewhere noisy and haven’t heard their phone ringing
They're not going to be able to hear a voicemail message either. But they can read a text.
They don’t actually want to speak to you
If they're screening their calls, they might well see your number, groan and decide not to answer. Leaving a voicemail will not make them want to speak to you any more than they already do. Trust me on this.
Other reasons why you shouldn’t leave a voicemail:
The recipient has to pay to hear you. Pay As You Go users need credit to listen to voicemails, and if they’ve run out, they’ll have to get a top-up before they can access your message. And that might be inconvenient, or require cash they don’t have. (They can read a text free, instantly, although they still can’t reply until they’ve got credit.) This isn’t such a big deal for people on monthly contracts, but they will still have to pay to hear your message because most mobile phone plans don’t include voicemail pick-ups in their inclusive minutes.
A voicemail almost always takes longer to listen to than a text message takes to read, and you have to go through more steps before you can reach the actual content of the message.
Texting forces you to think about what you’re saying. The act of writing makes most people express themselves more clearly and concisely. Of course there are rambling, ambiguous or incomprehensible texts too, but ask yourself: do the people who send these express themselves any more clearly in speech?
Reasons you should leave a voicemail
You’re cycling somewhere and you need to leave someone a quick message. Your fingers are frozen and you need to get moving again quickly.
You’re driving and using your hands-free kit. (I hope you got a passenger to dial the number for you.)
You’re blind, or visually impaired. In this case, I know that the alternatives are fiddly. I don’t want an option that’s convenient for me but massively inconvenient for you. Also, most of the visually impaired people I know tend to express themselves very clearly and leave concise, to-the-point voicemails.
You have RSI. I remember when mine was at its worst, I had to overcome my natural fear of making phone calls or I couldn’t have got anything done. I hated leaving voicemails, but writing a text was slower than piping icing onto a cake.
You only have a landline number for the person you’re ringing. Yes, you could text it, but a lot of people hear the texts-to-landlines robot voice and immediately assume it’s phone spam, so they delete the message without listening to it. (Also, the robot voices read kisses out as “EX EX EX”, which is a bit embarrassing.)