Explain briefly why musical instruments often appear in cubist paintings. my explanation ; musical instruments appear often in cubist paintings due to their uniquely geometrical designs. cubism, founded in paris during the beginning of the twentieth century, grew out of frustration with the more realistic forms of art of the late nineteenth century. it was considered one of the landmarks of the beginning of the modernist movement that was centered in paris and that tried to radically redefine a variety of art forms. picasso was considered the ultimate modern artist.