In a SIPOC diagram, why must the 'Outputs' be defined strictly from the perspective of the customer rather than the internal process owner?

In a SIPOC diagram—a high-level tool used to map Suppliers, Inputs, Process, Outputs, and Customers—defining Outputs from the customer's perspective is essential because the primary purpose of any process is to deliver value to the recipient. If an internal process owner defines the output based on what they find co....