Why is it important to have distinct vanishing points when using perspective?

Answer 1

Hey there...
The vanishing points is there to create the illusion that the object has depth and also visually it represents the object in 3d.

In drawing it is used as a guide to assist with the construction of the 3d model. It is also used in Architecture and Technical drawings. Like isometric, demetric and trimetric drawings.

If the points is not set to the horizon then the drawing is out of proportion and the eye will pick up that it is not realistically proportioned.

Hope this info gave an idea why the distinct vanishing points is of imports
Cheers.