The dynamic development of technical culture results in people of all ages and walks of life spending most of their life in the company of technical objects. These technical objects are characterized by a determined range of adaptation to human mental and physical abilities. Their construction presents requirements that might significantly lower ease of use or user efficiency – depending on the given situation. This frequently occurring imbalance between the requirements of technical objects and the expectations of their users often results from the element intermediating in the communication between these parties. This mediator is the interface, as well as the conditions surrounding this process, i.e. the socalled situational context that accompanies this interaction. The regimen of production systems and quality systems can ensure the production of ergonomic technical objects, however the range of ways for humans to use them remains unlimited. This range is connected to individual (personal) predispositions and the conditions in which the user is using the given technical object. Scientific publications from the field of ergonomic diagnosis of human-machine systems provide knowledge that is helpful in the assessment of important factors that reduce the ergonomic quality of technical objects. They facilitate establishing the importance of the situational context for the efficient functioning of man that uses technical objects in everyday practice and initiates interactions while controlling these objects.