I was pleasantly surprised when I got a correctly oriented preview by picking just 2 points to construct a plane, you needed 3 before, however this is still the case because when you click on "OK" it says: "input is incomplete"

I understand the preview is meant to give you an idea of how the new plane is going to form as you continue selecting references, but the fact that it lies correctly makes it sort of annoying that it won't build like this.

Where is this assumption taken from? How can the plane know for the previewing? Because it's spot on where I want it.