Well, because it’s not a “work” at all but a pastiche whose one and only intention is to deceive. Its maker—reportedly, a guy in a garage on Long Island—wasn’t concerned with emulating the historical Rothko but, instead, with mirroring the taste of present-day Rothko fanciers. Fakes are contemporary portraits of past styles. No great talent is required, just a modicum of handiness and some art-critical acuity. A forger needn’t master the original artist’s skill, only the look of it. Indeed, especially in a freewheeling mode like Abstract Expressionism, a bit of awkwardness, incidental to the branded appearance, may impress a smitten chump as a marker of sincerity—even as something new and endearing about a beloved master.
Time destroys fakes by revealing features of the era—the climate of taste—in which they were made.