A navigation system is not normally changed for social reasons. When changes are made, they are intended to meet new or more stringent requirements, to utilize technological advances, to increase efficiency, to improve safety, or to extend the functions which can be fulfilled. Innovations are evaluated according to their technical feasibility and cost. Not only have social factors failed to influence the nature of changes, but the social implications of changes have also been ignored. Yet greater benefit would often accrue from changes if their social effects were predicted and allowed for. Such predictions are usually feasible.

Social problems in navigation systems are gradually becoming more severe. In the past, man could often compensate for their effects because his role remained sufficiently dominant for him to be innovative and flexible in resolving difficulties, and he retained a full understanding of the system and control over it. More recent aids tend to curtail human communication, restrict the nature of teamwork, and reduce the social aspects of such functions as consultation, supervision, and verification. Man-machine relationships are emphasized, instead of relationships between people. Each man tends to be more remote from his colleagues, and to know less about what they are doing. These effects are generally incidental rather than the reflection of a deliberate policy.