inattentive to the road's needs
The official reason the chicken crossed the road.
After years of intense psychotherapy, the road's psychoanalyst penned his conclusive diagnosis "the chicken unknowingly committed a grave error, transitting from its permitted location to an unsanctioned area, pathologically and permanently violating the delicate psyche of the highly sensitized patient, because it was perceived as an inconsiderate act and extremely inattentive to the Road's needs. Alas, the patient is destined to be similarly crossed by many, if not most, of those it may expect to encounter in the future."