Angry customers will often come at you with a negative tone and accusatory language. They are convinced, before they even picked up the phone, that you aren't going to be helpful. They are expecting to have to claw, bite and fight for any kind of resolution. Usually, by the time the customer has reached this point, it's because our service delivery system has already failed them, perhaps multiple times.
While it's hard not to react to the customer with the same attitude, the fact is that a similar response is only going to escalate the customer further. If the customer starts the call by being snippy and accusatory and we respond in an equally accusatory or snippy manner, the customer thinks, "Aha! I was RIGHT! They ARE going to be difficult to work with. I have EVERY RIGHT to get ticked off and yell at them!"
We can't control how a customer is going to react or respond to us. We CAN control how we react and respond the customer. By refusing to respond to the customer in a similar angry, snippy, accusatory manner, we will often give the customer no place to emotionally go with their anger. They want to get angry, scream and yell, but if we refuse to respond in a like manner, the caller will often begin to calm down.
But, we're not done.
There's an old proverb that goes like this: "Bless those who curse you, and in so doing it will be like heaping burning coals on their head." In other words, if you act the opposite of the customer by being extra nice, friendly, helpful and attentive – you will frustrate their desire to be angry. The customer begins to think, "I'm going off on this person, but they're being nothing but kind and helpful to me!"
I've heard many calls through the years in which a CSR calms and angry customer and turns them around. It is almost always because the CSR refused to react in anger, and instead they proactively "killed 'em with kindness" by being appropriately friendly, empathetic and helpful.