No people, no value
Have you ever considered that things lose meaning and invariably value when people lose interest in them? There was a time when the Nokia 3310 was the phone to have and the craze of the moment, but interests have since shifted to the epic iPhones.
No matter how good a product or commodity is, if there are no people interested in it, or available to buy it, then it becomes nearly worthless in value. It is true there are some things that people cannot live without, like food and water, but if you had a warehouse full of such supplies in the middle of a remote island that no one could reach, then although what you had was very valuable, the absence of people would make it worth nothing.
I reiterate again, the only reason why things hold value is because people want them. If you want to build your financial gains, the secrete is to follow the people and thier interests and not necessarily the things they are interested in today. Study people for long enough, market research, and you will be on to the next big product. Ignore people, and you will soon be left with a pile of worthless options.