When an agent gives me three options and I pick B, I used to only save B.
That was the wrong half. Why I threw out A and C is usually more useful. Too generic. No evidence. Wrong stage for the company. Or I just do not want to be that kind of company.
After twenty or thirty of those notes, the reasons stop looking random. They cluster. Same three or four failure modes keep showing up.
For research drafts mine were: reads like a book report, hangs on one source, citations look complete but I never checked them. I thought the agent was dumb. Those three lines were my acceptance bar. I had never written them down, so I had to explain them out loud every time.
Now I keep the veto reasons. The agent still misses. But next task I can state the bar up front instead of arguing after the work is done.