This note investigates a recent paper by Yao et al. and a critique by van der Vlist et al. Both papers presented interesting arguments to show their findings and conclusions. However, their conclusions about the buyer's order sizes seem to conflict with each other. Revisiting both papers, we come to the conclusion that both papers are valid within the scopes and assumptions of their studies. Our paper summarizes the factors that must be stated clearly to resolve the conflict and to avoid the confusion.