The relation between the firms and the customers depends upon the type of services or the products that are being offered. If a firm is more likely to sell its product or service as Sales-as-a-service (SAAS) model then there is need of high customers interaction and maintain the loyalty of the customers and if the product is like construction materials like bricks, concretes then there is less need to carry on with customers.
The transactional selling like in construction materials do not need long term customer relation, not sold the same products frequently, the customer is more into prices so in such selling, the firm does not need to have a large sales force.
The strategic partnerships need high customer relation, the need of customers and the capability of the firm to fulfill the need highly cooperate. The strategic partnership needs to work closely with its customers so that it can maintain a high level of trusts and keep its loyal customers within the firm's product lines. Since it is not one-time sales and it needs to go on continuously with the shared vision, benefits, and goals, the strategic partners need to have a higher sales force in comparison to the similar sized firm with transactional selling.