"technological momentum" takes the two models and adds "time" as the unifying factor. in hughes's theory, when a technology is young, deliberate control over its use and scope is possible and enacted by society. however, as a technology matures, and becomes increasingly enmeshed in the society where it was created, its own deterministic force takes hold, achieving technological momentum in the process. according to hughes this inertia, which is particularly the case for large technological systems with their technological and social components, makes them difficult to influence and steer as they start to go more on their own way, assuming deterministic traits in the process. in other words, hughes's says that the relationship between technology and society always starts with a "social determinism" model, but evolves into a form of "technological determinism" over time and as its use becomes more prevalent and important.