Persuasion is used to build and win credibility Public communications. Third parties often monitor communications between buyer and seller. Third parties might or might not have direct influence on the communication. They are constantly affecting perception by how they communicate among themselves and to your customers. Their communications can alter your perception and belief in the company with which you are working.
Journalists are one of many third-parties who monitor communications between buyer and seller.
When journalists directly affect relationships between a company and the key audiences on whom it depends for it survival and success, then media relations are essential. Conversely, when they don't, they are not. When companies don't need to deal with the media. When companies have to deal with the media. A company whose economic might is so great that society cannot ignore its presence.