The relative value of optical security features submitted to 1st line inspection - performed by the layman - depends on how easily they are memorized, recognized and identified. The relative security value of different Diffractive Optically Variable Image Devices (DOVID), under this type of inspection, depends on the same criteria taking specific forms for such kind of dense and dynamical visual elements. For DOVID, the relevant security components include image complexity, resemblance to other images, easiness of inspection, interconnection to product characteristics, and others. In this paper we review and analyze such kind of properties and how they can be used to implement a quantitative measure of the 1st line security value of DOVID, encompassing a number of constrains and specifications derived from human ergonomic factors. These insights are integrated in a broader context of an evaluation model of the security value of DOVID, elaborated through Multicriteria Decision Analysis methodologies, already assessed for 2nd line inspection.