To effectively detect objects of varying sizes, an object detection system can generate anchor boxes at multiple scales by utilizing feature maps of different spatial resolutions. Intuitively, smaller objects are more likely to appear on an image than larger ones; for example, a $1 imes 1$ object can appear in more possible locations on a given image than a $2 imes 2$ object. Therefore, a larger feature map provides more individual spatial units, allowing the system to uniformly sample a greater number of regions. This dense sampling is highly suitable for generating smaller anchor boxes to detect small objects. Conversely, by reducing the spatial dimensions of the feature map, the system samples fewer regions, which is ideal for placing larger anchor boxes intended to capture larger objects.