For years email subscribers were just a commodity – a tool used to achieve more sales. But in most businesses, sales targets are relentless – coming year after year with bigger expectations. You soon realise you’ll never get enough new customers fast enough to plug the gap of the torrent of people unsubscribing, let alone hit the ever-increasing targets

The risk of unsubscribers doesn’t seem obvious to start with. You know they’re there but the rates don’t appear alarming and when represented as a percentage of your total database – they’re tiny. However the slow drip becomes a steady flow and you soon find you’re going nowhere fast when it comes to increasing your database.

Your total number of email subscribers stagnates when new subscribers only just cover the unsubscribers. It can all mean that your hard work in recruiting new email recipients results in you simply treading water.

What’s more alarming is that many soon realised that unsubscribes are only a tiny piece of the picture.

The real damage to a database can be seen when you start looking at metrics that take into account how many people on your database are active – having purchased, opened, or clicked within a certain time period. When typically only 20% of people are opening and clicking on emails, what are the other 80% doing? Often it turns out they’ve done something worse then unsubscribe – they’ve simply disengaged.

These inactive people are the silent unsubscribers. To them your email messages have become wallpaper and they can’t hear you, however loud you shout. However pretty or enticing you make your emails they seem blind to your communication.

It’s pretty obvious why they turn off but you won’t realise it until you put yourself in the shoes of the customer. We don’t actually unsubscribe from emails until we’re really fed up. For the majority we just simply ignore them. In fact you have to push someone pretty hard before they press unsubscribe.

There are several stages beforehand – simply scrolling through emails without clicking moves on to not even bothering to open them. If you’ve got time you may even mark them as junk or move them to the promotions folder, but rarely will you actually unsubscribe.

We tend to reserve the unsubscribe button for the relentless and random – the likes of Groupon, JML Direct and the online specialist retailer you made a one-off purchase from.

Thankfully our Internet Service Providers (ISPs) such as Gmail do most of the work for us these days – monitoring which emails we engage with, prioritising the delivery of messages and automatically filing them in appropriate folders away from our main inbox.

This means we don’t have to unsubscribe ourselves, or even interact with what’s coming into our inbox. And as marketers we need to be mindful of this when it comes to regulating our own activity before we get blocked, lose our subscribers or simply get lost in the junk folder forever.

ISPs decide who reaches the inbox and all the tricks of the trade won’t protect you getting blocked or syphoned off from the primary inbox if your emails aren’t being read.

Some email clients are stricter than others but when one starts doing something, the rest tend to follow. Gmail are pretty stringent and it can be tricky to get visibility if you take your eye off the game. They delay the delivery of your communications if your engagement rates are deemed to be below par or even block you completely if they slip further.

It very difficult to get a true picture of deliverability by simply looking at your overall deliverability rate. It’s far better to look at your deliverability and engagement rates by ISP, examining the specific metrics for Hotmail, Outlook, AOL and Gmail one-by-one. If you see a sudden drop in one metric then address it fast. If you don’t, the other providers are likely to follow suit.

Good email service providers speak to ISPs and monitor your performance to resolve issues quickly. It’s far better to act when you start to see your engagement levels drop than wait and be faced with trying to resolve a block. This will leave your customers incommunicado whilst you try and sort it out.

So what does this all mean to the marketer?

Well it means that engagement metrics are not just a ‘nice to have’ – they are an indication of the health and the predictor of the future of your email marketing. So once you see your overall engagement levels dipping, what do you do?

The first thing is to stop associating a successful marketing database with size. It’s better to have 1000 people on your database if 900 of them are reading the emails than having 10,000 and only 1,000 recipients reading them.

Managing large, un-engaged databases puts a strain on resources when you’re creating email content which will never be seen, or segmenting and analysing irrelevant data and simply slowing up your CRM system.

If you’ve already got a large database then it’s time to be brutal. If you’ve calculated metrics such as open reach, sent unsuccessful re-activation campaigns or realised the lifetime value of a customer is low, then maybe it’s time to stop sending to them. Or at the very least be careful what you send to them and when.

So next time someone asks you how big your database is don’t be shy. There’s no point in maintaining a large database if it’s not working for you. And by burying your head in the sand and carrying on sending emails regardless of the response, you could be doing more damage than you think.

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