Instead they are fluid and reflexive. The father of virtual reality, Jaron Lanier, claims that his passion for inventing VR systems came from a long-frustrated urge to play "air guitar"--to be able to wave his arms and have music emanate from his motions. Anyone with access to a VR arcade can now have that urge satisfied, but it is a want that most people would have never recognized until they immersed themselves into virtual reality gear. It was certainly not a primary want that Plato would have listed.
At one time a useful distinction was made in economics between "primary" needs such as food and clothing, and all other wants and preferences, which were termed "luxuries." Advertising is undoubtedly guilty, as critics charge, of creating desires. At first these manufactured desires were for luxuries. But the reach of technology is deep. Sophisticated media technology first creates desires for luxuries; then technology transforms those luxuries into primary necessities.