This is important because the anchor point will make it easier to rotate text or other objects around a central point, you may need to rotate a text around a circle or other object to align it.

In geometry, transformation describes modifying the position, orientation, or size of a point, line, or shape. You can transform a shape by sliding it around on a coordinate plane (translation), ...

At some distant point, the rotation will be too much, and the light will turn around and return to the observer.