Final answer:
As the importance of a service dimension increases, the customer's tolerance for variance in that service narrows, and the gap between their desired and adequate service levels widens.
Step-by-step explanation:
When the dimension of a service increases in importance, a customer's zone of tolerance typically narrows, meaning they become less willing to accept variation in service levels. As customer expectations get more precise and their investment in the service becomes more significant, they demand higher standards and show less patience for deviations. Consequently, their perceived difference between desired and adequate service levels also increases. That is, customers have a clearer idea of what they particularly want (desired service level) and what they consider an acceptable minimum (adequate service level), likely leading to these two levels moving further apart. Therefore, businesses need to understand the importance of these service dimensions and manage them effectively to maintain customer satisfaction and loyalty.