Devotional reliefs of this period were often placed high up on the wall of a private residence or above the street, where passersby would have seen them from below.
In museums, devotional reliefs like this one are usually mounted at eye level. It makes for a more intimate point of view, and it is how Rossellino saw the relief as he carved it.
The relief provides a window between the everyday and the divine. The shallow carving of the angelic seraphim around the Madonna and Child suggests their otherworldly status.
Viewed from the side, the Madonna and Child are clearly carved in high relief, which suggests they are corporeal beings that occupy the same space as the viewer.