“My dog could have painted that!” Consider a white canvas with a single black square painted on it. Malevich's Black Square more specifically. When approaching a painting such as this in a museum, most viewers dismiss it for its simplicity. There is an adjustment when people view contemporary and modern artwork; even today people can't quite separate themselves from only considering the refined works of the Renaissance as "real art". Common comments might include "my kid could have painted that", "I could have painted that" or even "my dog could have painted that." Sadly, the viewer’s nanosecond judgment misses the point. Phrases like this are evidence of the fact that they have missed the point.
The true wonder of modern painting is innovation. The artist is a mind at work. The beholder needs to understand that the artist is more than a craftsman, a human camera. The artist is a mind at work. In the Renaissance, artists were philosophers, scientists, and historians: geniuses. Prior to Malevich painting a black square on a canvas and placing it on a wall, no one had done that before. This was a major innovation in the art world. So while now you connect with these works of art by recalling "doodling" the same series of squares and crosses on your high school chem notes during fits of utter boredom, what you might be missing is that your black square isn't original. Malevich's is.
Modern art history relies on the breaking of tradition. Consider Picasso. He is admired worldwide for his innovative paintings. Before he started the Cubism, though, he learned to paint formally. This is where art started, in the formal and realistic rendering of life, because there was no other way to record perfectly the historical events and portraits. The invention of photography broke that cycle so that if people wanted an exact rendering, they could snap a photo. Paint no longer had to be a translation of light. Artists like Kandinsky, Picasso, Malevich, and Pollock were the minds willing to find out what paint could do as its own media.
So the next time you go look at a painting that you think you could have done, just remember that you didn't; Malevich did.