Most regular readers know I think open and click through rates are actually proxy measurements. That is they measure things that correlate with reading and interacting with an email and can be used to estimate how much an email is wanted by the recipients.
The holy grail is, of course, having ISPs report back exact metrics on what a user did with an email. Did the user read it? Did it stay open on their screen a long time? Did the user just mark it read or throw it away? What happened to the message. Marketers would love this information.
It’s unlikely the ISPs will ever provide this information to marketers. Take away all the technical challenges, and there are some significant ones there are still social challenges to making this data available. Current user contracts protect the privacy of the user, local laws prohibit sharing this data. And, there is the vocal group of privacy advocates that will protest and raise a big stink.
I’m not sure why email is gets the special treatment of expecting the channel owners to provide detailed disposition data. In no other direct marketing venue is that information collected or provided. TV stations can’t tell advertisers whether or not someone watched a commercial, fast forwarded through it or got up to grab a beer from the fridge. The post office can’t tell direct mail marketers whether or not a recipient read the mail or just dumped it in the big recycling bin the post office provides for unwanted messages. Billboard owners can’t tell advertisers how many people read the billboard.
Since we can’t get exact read rates from ISPs, what do we do? We look at proxy numbers.
Read rate directly measures who opened the message. Open rate is a proxy. It’s who displayed images in the message.
Read rate can be measured only by people who have access to the user’s inbox. The ISPs can measure read rate because they have full access to the mailbox, but this requires the user to access the mailbox through webmail or IMAP. Some third party mailbox addons can measure it, but this requires the cooperation of the mailbox owner. If the mailbox owner doesn’t install the reporting tool, then the 3rd party doesn’t have access to the data. Only groups with access to the end users mailbox can measure this rate.
Open rate can be measured by people who have access to the server images are hosted. Senders and ESPs and 3rd parties can measure it if they provide unique image IDs or tracking pixels in their emails. Open tracking does require the cooperation of the recipient – they have to have images on. No images on, no open tracking. Ironically, ISPs cannot measure open rate, because they have no access to the image hosting servers.
Click rate can be measured by people who have access to the server that hosts the website. The same people who can measure opens can measure clicks. Some ISPs can measure clicks, Hotmail used to pass every URL through a proxy they hosted and they could count clicks this way. AOL controls the client so they could measure number of clicks on a link. I’ve heard trustworthy folks claim that ISPs are measuring clicks and that they’re not measuring clicks (any of the Barry’s want to comment?).
Without controlling the inbox, though, senders have to rely on proxy measurements to judge the effectiveness of any particular campaign. But at least email marketers have proxies to use for measurement.