A project manager was concerned the results were not fulfilling the expectations at the end...

When a project manager observes that the project's outcomes do not align with expectations, despite the vendor fulfilling all contractual obligations as per the Statement of Work (SOW), the appropriate next step is to perform a gap analysis. This analysis helps identify discrepancies between the current state (what has been delivered) and the desired state (stakeholder expectations).

According to the CompTIA Project+ PK0-005 exam objectives, under Domain 2.5: Given a scenario, perform risk management activities, performing a gap analysis is a critical activity to assess and address such discrepancies. The gap analysis will provide insights into areas where the project may not be meeting stakeholder expectations, allowing the project manager to develop strategies to bridge these gaps.