Why does Unreal Engine use both Sections and Components in Landscapes?

Hey guys,
In Unreal’s Landscape system, terrain involves quads, Sections, and Components, with Sections grouped inside Components.
If Components already handle things like rendering and streaming, what’s the reason for having Sections as an extra grouping layer? Why not just organize quads directly into Components? There is surely a reason, but I really don’t get it. Does anyone know why this extra layer of grouping exists? I mean, intuitively, what I think is why not group quads directly into Components, but instead we group them into what is called Sections, and then Sections are grouped into Components?