Which promotional method is often expensive because it involves direct contact with potential customers?

Personal selling is considered an expensive promotional method primarily because it entails direct interaction between sales personnel and potential customers. This method often involves one-on-one meetings, demonstrations, and extensive follow-up, requiring significant resources such as sales training, travel expenses, and time investment from skilled personnel.

Additionally, personal selling allows for tailored communication, which can enhance the likelihood of making a sale due to the ability to address individual customer needs and preferences. This level of personalized attention can further elevate costs, as it is labor-intensive compared to other promotional methods. Other options, while they may incur costs, do not usually require the same level of direct engagement or resource investment that personal selling does.