A gate is not a vibe check. It has a test that two people would run the same way, and a defined consequence. "Zoom to full resolution and read every word on the packaging; a fail returns to the master plate" is a gate. "Make sure it looks right" is a hope.
Gates are also what makes volume safe. At four assets a week, taste catches everything. At four hundred, only a checklist does, and the checklist has to name the failure modes that particular subject invites: labels for packaging, spoke counts for motorcycles, hands for anything held.
What quality checks should an AI production have?
At minimum: a likeness check for people, a label check for anything printed, a silhouette check for products, a light-direction check across a set, and a claim check so nothing invented ends up as a factual assertion.
Who signs off generated work?
A person, on the brief and on the final cut, at any volume. That is the human gate, and it is the one gate with no exceptions.