Explanation:

In Salesforce Industries CPQ, the Cart header does not show a running total of all purchases made by the customer historically. Instead, it displays information relevant to the current transaction — such as the total price of items currently in the cart, applicable discounts, and taxes.

The Cart is scoped to the active quote or order being configured, not the customer's full purchase history. If you need visibility into past purchases, you'd typically use:

The Assets tab to view existing products and services owned by the customer.
The Related Lists tab to access historical orders, contracts, and account-level data.

This separation ensures that the Cart remains focused on the current configuration session, while other components handle lifecycle and history tracking.