Excerpt from this article:
People who study complaints divide them into two categories, instrumental and expressive. An instrumental complaint is “directed toward a specific target and intended to bring about a specific outcome,” according to Robin Kowalski, a professor of psychology at Clemson University who has studied the social functions of complaining. Calling a restaurant’s owner the next day to say that you waited an hour for dessert and don’t intend to come back is an instrumental complaint. Texting a friend to say the polar vortex is making your skin peel off is an expressive complaint. We call expressive complaints venting, kvetching, griping or a number of other names.
It’s important to know which of the two types of complaint is right for you before opening the first can of invective. Venting has its uses. In one study, Dr. Kowalski and some colleagues showed that when we are asked to put our feelings of dissatisfaction with somebody into writing, our “positive affect” — good feelings, basically — will rise about 15 minutes later, after an initial downswing. In the same way, if a meal lets you down, taking a pair of pliers and a blowtorch to the restaurant on Yelp might give you a brief lift.
But once the rush of having gotten it off your chest is gone, you’d realize nothing has changed. You’re still out the price of dinner, and you won’t find out whether your grievance has reached the right ears unless somebody at the restaurant responds. Some owners make a point of scouring review sites so they can do just that. Others use the review’s date and details to identify and get in touch with the kvetcher. But there are more direct ways to get your gripe acknowledged than scrawling it on the walls of the internet.
“If there’s something that’s really bothering you, the ultimate benefits are going to come from targeted complaining,” Dr. Kowalski said. “Telling the person or restaurant.”