Why do clothing items labeled with a size range hang with the larger size in the range?
In almost all cases, if you hold, for example, a “12-18 month” item up to an item with a single size on the label (often department store brands), you will find that its dimensions compare more closely with the 18-month item, not the 12-month item. We do our best to get all the items that will actually fit a specific size into the same section.
