It can never be stable unless bitcoins are designed to lose value over time (that's why normal currencies are designed that way). Intrinsically worthless tokens

It can never be stable unless bitcoins are designed to lose value over time (that's why normal currencies are designed that way). Intrinsically worthless tokens engineered to have better than market risk adjusted, liquidity adjusted, real returns compared to real productive investment will always be unstable and fluctuate increasingly wildly as they get more popular. This is a direct result of physical limits of production. As people hoard worthless tokens, their price increases which causes people to hoard them even more instead of investing in real businesses with real production capacity. This causes production capacity to eventually drop which means there is less things to buy with all the tokens. If people start buying real things with their stock of tokens, these tokens will be chasing fewer goods which means prices will rise (tokens will lose value). This might happen suddenly when people notice that token value is droping and that there are tons of tokens waiting on the sideline ready to make it drop even further. People will try to get rid of them all at the same time before they're worthless which will cause their worthlessness. This drop will bring them closer to their natural intrinsic value of zero. The cycle can then start again, such is aggregate economics. The 1920s and 1930s suffered from this type of cycle but with gold instead of cryptocoins. It's important for the world's sake to not let deflationary currencies become too popular. When savings or financial promises are insufficiently tied to future production or to accumulation of real goods, there will be disappointment when people try to exchange them for real stuff. That is true for crypto currencies as well as government currencies (that is why the system is designed to make banks invest people's money in real businesses and minimise the amount of money that is stockpiled idly).