Engage sophisticated audiences by telling them an email is *not* for them. Subject lines like "not for advanced marketers" or "ignore this if your conversions are strong" subconsciously challenge their expertise and ego, compelling them to open the email to prove the statement wrong.
To combat users' rapid 'social scroll' behavior within their email inbox, use subject lines that disrupt their scanning pattern. Phrases like "wait... this worked?" or "okay... this surprised me" create a crucial millisecond pause, which can radically increase email open rates.
Many marketers mistakenly summarize their entire email in the subject line, removing any incentive to open it. To increase curiosity, provide only a hint or a compelling data point from the email's content. This creates an information gap that subscribers feel compelled to close by clicking.
Contrary to old email marketing wisdom, testing fully capitalized subject lines can significantly increase open rates by 3-4 percentage points. Modern spam filters are less likely to penalize this tactic, making it a viable test for grabbing attention in a crowded inbox.