Well art is a way to express your self so if people are critiques about it then they may not understand it. So if I were in there shoes I'd feel kinda wouldn't care because it's my artwork about my emotions :) hope I helped ya
Art is subjective, but can be critiqued differently based on who is critiquing it. Different people have different opinions and standards of good art work. Many artist choose to reject formal skill and have a more emotional approach. This could be because they do not want to feel restricted and want to express themselves freely. I like this kind of art, I feel like this type of art allows for deeper emotion and feeling.
Op art designs are usually geometric patterns used to create an illusion. Im not really sure what you mean by "how say two artists that drow these things"
