What influences design?

To summarize the textbook, the primary force in influencing product design in a nation where product design is a major industry (developed country, free market economy) is desire. Wants and needs control economies, and in most developed countries, most people have most of their actual needs met. therefore want people want is a huge factor, and -- it seems to me -- a rather cyclical factor. Much of what people perceive as needs come from advertising and media that play on the idea of creating a better life. Fashion, color ways, patterns, and line styles are in constant flux so product designers often use the fashionable aesthetic in conjunction with a novel improvement on former products or processes to create desire. An emerging aesthetic is that which plays towards mindfulness, eco friendliness, and efficiency. This comes in the context of environmental degradation and massive material science advances, so one could argue that environmental factors and scientific pursuits are major design influences as well. People today are more conscious of what happens at the end of the life of their product, so when a product can be made cost effectively with recycleable material it becomes a selling point for desire, more than it is a necessary tool for sustainability. So the cycle repeats. There is eco conciousness, and new materials, so a product is advertised as the future, as better, as necessary. People see this happening, recognize the fashion and desire to be a part of it, creating a demand. This is a cynical explanation for an example of a good and beneficial trend, but it is nonetheless true. Even our desire for a sheer volume of things, useful or no, is a manufactured symptom of a consumerist economy.