Email marketing
The metrics that lie: Open rates and clicks. "Open rate" corresponds to how often an email is opened or viewed after the recipient gets it, and "clicks" are when the user clicks on a link in the email itself.
The myth: A common practice among email marketing is A/B testing, which means that two nearly identical emails are sent out to different groups of people simultaneously. There will be one subtle difference between the two, such as a different subject line. The idea is that the version that performs better has a more desirable subject line. This can help the copywriter write more effective subject lines in the future. Many assume that the "winner" email is the one with the best click rate, open rate, or both.
What they actually measure: Only one piece of the picture is being seen here. Remember that these numbers only tell you how many people viewed the email and how many times links were clicked. So what happens after? If you only want the recipient to see something, mission accomplished. But most people need that user to then take an action (such as buying something), and open rates and click rates don't address the next steps.
How to avoid being fooled: Remember that it's all about the quality of the click and its ability to convert to a sale or a conversion (or whatever it is that you want the user to do). Let's say that 1,000 emails are sent, and the "loser" email gets a 2 percent click rate (20 clicks) while the "winner" email sees a 10 percent click rate (100 clicks). If the "loser" email converts 60 percent of the clicks into sales (for a total of 12 sales), and the "winner" email converts 10 percent of the clicks into sales (for a total of 10 sales), then the "loser" is clearly the winner, in the sense that it resulted in more sales.
Tips for next time: Know where in the "life cycle" they are, and attempt to market with a specific message
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