Everybody is their own self and we may all see things differently. Although we see things differently, my results show that everyone finally does see the illusion. It may take a while, but finally all see the illusion. Some people just do not see anything, but with a little help they too can see the illusion. I guess it just depends on you.
Illusions are just errors in perception of the illusion.
They are differences in the appearance of a measurable aspect of the world such as size, distance, and shape. Sometimes there are hidden things in a picture. There may be another picture or a design inside the original picture. We get used to how things are supposed to be, and sometimes our brains get the clues all wrong. Our brains put images together because they have learned to expect things, and sometimes the data might get a little confused.