I have a question, Why currency value changes, and falls?
Supply and demand; people speculating on near and medium-term future value of the asset.
Why sell currency at $ 450, and not wait ten years to sell it priced inhaled million?
The smartest people in the room are doing precisely that. Although in 10 years you won't need to sell it, you'll just use it.
As for the rest, it's fear, mostly. Also, food and rent can't be paid in bitcoin yet.