You cannot peel an orange and lay the peel flat without tearing it. Earth has the same problem: every flat map distorts something — area, shape, distance, or direction.
The gold circle covers the same real land everywhere — on the globe it is always round and one size (that is Tissot's indicatrix). On the flat map it shows the lie. Mercator keeps shapes round but blows area up toward the poles — which is why Greenland looks bigger than Africa, though Africa is about 14 times larger.
Slide to equal-area and the size stays honest everywhere — but now the circle is squashed and sheared. No projection can keep both size and shape. That is a mathematical impossibility, not a missing invention. Every map just chooses which lie to tell.
Something in the simulation stopped unexpectedly — the lesson continues without it. Nothing you did was wrong; you can move on.