Treat the long video as raw material, not as something to summarize. Mark self-contained moments with a strong hook and payoff, cut each into a vertical-native clip, then rewrite the opening, captions, and packaging for each platform.
Some revision is normal, but endless revisions usually point to a broken briefing and approval system before they prove the editor is a bad hire. Lock the style, decision-maker, script, references, and feedback process before judging the person.
If one video takes around 100 hours, stop treating every edit as a showcase of every technique you know. Set a quality floor, prioritize story and packaging, reuse assets, time-box polish, and delegate repeatable editing stages if the workload is blocking consistent output.
Delegate tasks that are repetitive, time-consuming, teachable, and easy to review before you delegate the creative judgment that makes the content yours. Editing, thumbnails, clipping, formatting, scheduling, asset management, and production admin are common first handoffs.