A brand promise goes beyond a catchy slogan or tagline. It is a commitment to the audience to deliver the solution offered. In making that promise a brand puts its integrity on the line and in breaking that promise the integrity is tarnished.
FedEx is known for their promise (which is also their slogan) “When it Absolutely, Positively has to be there overnight”. If you used FedEx consistently and one day, your parcel didn’t make it to its destination you might think “That’s not like them” and put it down to a one of. If the next month they did it again, and then again the following month, your trust in their promise would diminish considerably and chances are you would begin to consider alternative solutions.
Only by keeping the promise, day after day, week after week, month after month, year after year, does a brand earn long-standing trust from its audience that breeds brand loyalty.
Even if the brand has delivered on its promise consistently over time, one instance of a broken promise can have a major impact on trust.