1. An authentication system, comprising: an image capture device to scan an object, wherein the object is an accessory of a user; a processor; and a machine-readable storage medium storing instructions that are executed by the processor to: generate model data that represents a template of imperfections associated with the object during an initial enrollment of the object; identify current imperfections in the object based on the scan, wherein the current imperfections are from at least one of a manufacturing process or wear and tear; compare the current imperfections to the template of imperfections of the model data; determine that a correspondence between the current imperfections and the template of imperfections of the model data is above a predetermined threshold; authenticate the user when the correspondence is above the predetermined threshold; and configure a device based on preferences of the user when the user is authenticated, wherein if the comparison of the currently identified imperfections to the model data exceeds a predetermined threshold and new imperfections are identified, the model data is updated with the new imperfections, wherein if imperfections in the model data are missing from the currently identified imperfections and the comparison exceeds a predetermined threshold, the object is re-enrolled and new model data for the object is generated.