Start from the source defect, not the 4K label
The Standard route is a practical test for clips that are small, softly encoded, or visibly compressed. A reasonably clean social export, screen recording, product spin, archive excerpt, or proofing clip may gain clearer edges and a more usable presentation. The route cannot recover a face hidden by motion blur, restore clipped highlights, rebuild unreadable lettering, or reverse severe prior editing with factual accuracy.
Inspect the source at normal playback speed and frame by frame before spending credits. If the main problem is camera shake, missing frames, incorrect color, damaged audio, or a watermark, upscaling is not the complete repair. Fix those issues in an appropriate editor first, then use the strongest lawful master available as the input. Repeatedly upscaling an already artificial output usually compounds halos, invented texture, and compression residue.