I want to know the answer to the following question:
What facilitated the success of Operation Roundup?
All the background I'm provided with is that "The PVA had outrun its logistics capability and thus were unable to press on beyond Seoul as food, ammunition, and matériel were carried nightly, on foot and bicycle, from the border at the Yalu River to the three battle lines.". Is that enough to answer the question?
Answer: no