You got more than you bargained for.
Ever notice that phrases like these mean something negative when on the face of it, they shouldn’t? You pay for something, and you get it. Naturally. You bargain for something, and get a little extra. Who wouldn’t be happy about that?
Yet these phrases don’t mean good things. These phrases mean there’s an unanticipated shortfall in the deal, and you’ve been shortchanged in one way or another.
Money-back guarantee. In other words, if you don’t get what you’re supposed to, you can return it for a refund. This is your bare-minimum: both sides of the ledger balance out, one way or the other. Dollar-for-dollar, equivalent value.
And it’s completely, entirely unremarkable. Even the buy-one, get-one-free or other discount offer is unremarkable. It’s as advertised: no more, no less. Not worth mentioning.
If you want to be remarkable, give the client something extra, something they weren’t expecting. Imbalance the ledger in their favour, go the extra mile. That’ll be memorable — and worthy of remarking upon. Much more than simply giving what you were paid for… that only gets you damned with faint praise.