Loan origination workflows require API orchestration, not aggregation, due to their sequential and dependent nature. API aggregation uses a fan-out/fan-in model for independent services, returning a unified object quickly. Loan API orchestration, however, manages a sequence of dependent calls, maintaining state and executing conditional logic. This distinction is crucial because lending workflows have explicit step dependencies, such as identity verification before credit pulls. Failing to recognize this structural reality leads to incorrect integration stacks. Aggregation is suitable for dashboards or analytics where service calls are independent and failures don't halt the entire process. However, in loan origination, a failure at one step stops the workflow entirely, requiring precise state management. Using aggregation for orchestration results in lost approval rates due to inability to manage multi-lender submissions concurrently. It also creates compliance risks by failing to enforce timing requirements for disclosures and adverse action notices. Orchestration allows for strategic parallelism at safe steps, optimizing decisioning speed. It also enables robust error handling and state recovery for stalled or failed API calls. A correctly structured orchestration architecture like FinMkt's manages the entire origination sequence as a single workflow, ensuring speed and compliance. Incorrectly applying aggregation to orchestration leads to compounding costs, operational backlogs, and competitive disadvantage. Understanding loan origination as a coordination problem from the design stage is essential to avoid costly rebuilds.