Final answer:
The next step should be to implement the critical recommendation identified in the quality audit to ensure successful product delivery to the customer.
Step-by-step explanation:
If a critical recommendation affecting the successful delivery of the product to the customer has been identified in a quality audit, the next step should be to take action and implement the recommendation.
This may involve making changes to the project plan, processes, or resources to address the issue and ensure the successful delivery of the product. It is important to prioritize and act promptly on critical recommendations to avoid any negative impact on the customer's satisfaction and the project's success.