We can all agree that when a retail company subject line says, "Surprise, sale extended!" what they're really saying is, "We didn't sell as much as we thought so we're gonna try and keep this going."
Some of these companies may be responding to genuine consumer demand (and not just trying to ensnare you with clever marketing trickery). So how can you tell the difference?
You can't.
As a customer, you're either going to ignore it or fall for it.
As a business owner, the lesson here is that sometimes we have to sacrifice cleverness for clarity. I’ve touched on this notion before (see: “Kill Your Darlings”). Catchy subject lines are all fun and games until they confuse your customers. Be clear with what you're offering and why you are offering it. It’s the best way to ensure your content doesn't get lumped in with the latest "marketing hacks" and clickbait headlines.
Remember, your customers want to hear from YOU (not the marketing expert who taught you how to write a snappy headline). Beware tactics that come across as anything but authentic.