Why do Cycles renders faster when the render window is zoomed out

I think we need to clarify something here, because we’re getting answers with two fundamentally different sets of assumptions about the conditions Atom is describing. Atom, when you say “the render window is zoomed out” do you mean:

A) in the 3d viewport, the camera is zoomed out away from the object you’re rendering, such that the object is small relative to the total scope of the rendered image?


or

B) the window that displays the render result is “zoomed out,” meaning the actual render result image appears small relative to your screen, so you need to roll your scrollwheel to enlarge the image?