Nothing breaks a campaign faster than a model whose face changes between shots. Identity preservation is now a solved problem, if you feed the model the right references.
Reference discipline
Lock one canonical portrait: front-lit, neutral expression, high resolution.
Attach it to every generation in the set. Never describe the face in words alone.
Change one variable per shot: pose, wardrobe, or setting. Not all three.
Where it pays off
Campaigns: one talent across ten placements without a reshoot.
Serialized content: a recurring character your audience recognizes.
Localization: same face, different market, different wardrobe.
Consistency is a workflow property, not a model property. The reference file is the contract.