I just put 13 thumbtacks on the wall in no particular order.
Twenty minutes later, from the other side of the room, I noticed the final result had been straight diagonal lines, top left the down right. This was not intentional nor does it reflect the order in which I put them on the wall.
I went closer to check it out and realized they were in even straighter lines when viewed top right to down left.
But back now at the other side of the room, I cannot see those lines. I can only see the others.