Reality is subjective - for abstract artists. Abstractionists utilize a visual dialect of shape, frame, shading and line to create a structure which may exist with a level of freedom from visual references in the world . Abstract art does not portray a person, place or a thing in the natural world; or it does, but does nor make any visual references. Abstract art never vanished - it just took diverse shapes relying upon what movements we are talking about.
"Of all the arts, abstract painting is the most difficult. It demands that you know how to draw well, that you have a heightened sensitivity for composition and for colors, and that you be a true poet. This last is essential." - Wassily Kandinsky