We promise to never pass on your email address to anyone else.
When credit cards were new on the scene the major players were spending big bucks recruiting new card holders.
Amex used exclusivity as their USP. The opening sentence of a much mailed letter read:
“Quite frankly, the American Express Card is not for everyone. And not everyone who applies for Card membership is approved.”
Snobby, yes, but this was their control letter for years. Would it work today? I don’t think you could phrase it in the same way but I do think there is a place for including exclusivity in some form into your copy. Hyacinth Bucket from “Keeping Up Appearances” (who insists it's pronounced "Bouquet") would have loved it.
I am also reminded about a painting my wife and I admired at a gallery. We were happy to go home and consider the purchase but when we heard another couple raving over the same picture I went and bought it on the spot. The thought of missing out was too much for me. Considering this later, the cynic in me was convinced the other couple were a “plant”, there just to speed our purchase.
So when you’re considering some new copy to test have a look at the “exclusivity” or the “fear of missing out” angle. It might be ready for a come-back.