The contract defines what was promised. The question is whether anyone on your side is tracking whether those promises are being kept.
The vendor committed to deliverables, timelines, resource levels, and quality standards. Are they delivering what was sold, or has the gap between promise and reality been quietly accepted?
When problems arise, you need to know early. The question is whether the vendor surfaces issues proactively, or whether you only find out when it is too late to act.
Scope creep is the primary driver of cost overrun and schedule delay. The question is whether you can evaluate whether a change request is genuinely required, or whether it serves the vendor's commercial interests.
Critical issues test whether accountability is real or performative. The question is whether the vendor takes ownership when things go wrong, or deflects responsibility to your team.