In modern art, the boundaries between artist and spectator are often blurred as the spectator is engaged in the interpretation process and thus in the creation of an artwork, a process referred to by Marcel Duchamp as the "transubstantiation" of objects into art. However, this communication of artistic intent provides room for error, misinterpretation, and reinterpretation (accidental or intentional) of the artwork's intended meaning. Duchamp refers to this as the "art coefficient," which is mathematically explained as the difference between the artist's intended, unexpressed idea and what they unintentionally expressed. The idea of artistic intent, or lack thereof, was toyed with by Duchamp and the artists who followed in his footsteps, including some protagonists of the post-WWII Croatian art scene (Ivo Gattin, Goran Trbuljak, Braco Dimitrijević, and Tomislav Gotovac) who were involved in emerging art movements such as Art Informel, Conceptual art, and the neo-avantgarde, respectively. This paper puts forward works by Croatian artists who experimented with (un)intentionality and haphazardness by employing new artistic techniques, leaving room for (intentional) error and chance, or challenging the artist's and spectator's role, often by exploiting the latter to do their work for them.