Why did Marcel Duchamp say that he had not known about Futurism while painting Nude Descending a Staircase (No. 2)?

While Nude Descending a Staircase (No. 2) is frequently associated with Futurism due to its depiction of motion through successive, superimposed images, Marcel Duchamp maintained that he was entirely unaware of the Futurist style while creating the work in 1912.12

Duchamp’s development of the painting stemmed from his own experimentation with movement, which he felt was missing from the Cubism of the time. He found Cubism to be too static and systematic, leading him to seek a "nonobjective" expression of motion. His approach evolved from earlier works like Portrait (Dulcinea), which utilized superimposed silhouettes to capture movement, eventually culminating in the cinematic, machine-like effect seen in the Nude.23

Although critics and viewers often categorized the painting as "Cubo-Futurist" due to its harsh angles and aggressive energy, Duchamp’s artistic trajectory was driven by his personal rejection of traditional painting constraints rather than an adherence to the specific tenets of the Futurist movement.123