The problem with the notion of “brand promise” is that it places the origin on the sender rather than the receiver. The fact that you tell me that I can trust you (i.e., a promise) does not mean that I actually trust you. In fact, I might even have a negative response to the claim.
We need a notion of brand that starts with the receiver, and that takes the form of an expectation as opposed to the form of a promise. Brand represents the aggregate experience of the value proposition — not just my experience as a customer, but the market’s experience, and the reputation associated with the same. That experience fosters an expectation, and the brand must deliver on that expectation.
A promise does not have the impact of an expectation because a promise originates with the sender, whereas an expectation originates with the receiver — and thus is more powerful. Brand delivery works better when we understand that it is not about making a claim, but helping a prospect arrive at a conclusion. People challenged with a claim naturally resist it. But people who arrive at a conclusion will naturally defend it.