Every imperfect render poses the same question: fix it here, or start it again? The studio answers with two questions, in order, and they route almost every frame correctly.
Question one: is the composition right?
Composition means the subject, the pose, the setting, the light — the photograph underneath the details. If any of those is wrong, no bench saves you: the editor cannot move a woman across a room, the upscaler cannot relight her, and a face swap keeps the wrong scene. Wrong composition means re-render, and the thing to fix is the brief — usually the clause you left vague. This is the expensive answer, which is why drafts are made at standard prices.
Question two: what, exactly, is wrong?
If the composition holds, name the defect in one sentence. A local defect — the dress is the wrong colour, a stray object sits in the corner, the necklace changed — is an editor job: 21 credits, original kept, one surgical brief. A wrong face on a right frame is a face swap: identity is a layer, and swapping the layer is cheaper than reshooting the scene. A right frame at the wrong size is neither: it is finished work waiting for the upscaler, and it should arrive there only when nothing else about it will change.
The order of operations
Re-render for composition, edit for defects, swap for identity, upscale for size — and in that sequence when a frame needs several. Each stage is cheaper than the mistake of doing it at the wrong stage: upscaling a frame you then edit throws away the upscale; editing a frame you then re-render throws away the edit. Finishing is last because finishing is the price of being done.