It is true that there has been controversy about the preferred method for people to make a complaint. I am convinced that both written and direct complaints have their own advantages and should be used in appropriate situations to be optimal.
To begin with, a written complaint serves as an effective means to communicate one’s concerns from a distance. Conveying dissatisfaction through emails or letters could eliminate the need for complainants to physically travel. This is particularly appropriate when dealing with foreign sellers who may be geographically distant, solving infeasible in-person communication. Moreover, it would be easier for people to keep calm and express their disappointment in a composed and formal manner by affording them the time to initiate a complaint thoughtfully and precisely. Thus, it would facilitate a more comprehensive understanding by service providers.
On the other hand, some individuals may find a preference for expressing their complaint in person, which is derived from the urge to receive an immediate response. Especially, when it comes to casual situations that do not require extensive documentation, direct conversation would enable swifter and more sympathy negotiation among involved individuals. For instance, when a person bought some merchandise that did not work well, they could return them to the seller and then either get an alternative product or get a refund.
In conclusion, I infer that the decision to choose whether a written or spoken form of complaint heavily depends on the individual’s communication preferences and the specific circumstances in which it arises.