It might be worth calling attention, then, to a paper by the 20th century sociologist Robert K. Merton, who in 1936 published an essay in American Sociological Review, titled, “The Unanticipated Consequences of Purposive Social Action.” (Merton helped popularize the theory of unintended consequences.)
In citing some of the major factors of unexpected consequences, Merton listed ignorance and error. About the latter, he wrote the following:
Error may also be involved in instances where the actor attends to only one or some of the pertinent aspects of the situation which influence the outcome of the action. This may range from the case of simple neglect (lack of systematic thoroughness in examining the situation) to pathological obsession where there is a determined refusal or inability to consider certain elements of the problem… In cases of wish-fulfillment, emotional involvements lead to distortion of the objective situation and of the probably future course of events; such action predicated upon “imaginary” conditions must inevitably evoke unexpected consequences.