I agree. However, I think a stablecoin becomes useful already if it is able to swing back in a relatively short time from an "overpriced" or "underpriced" phase to the "target price". The key is the ability of the "stablecoin" to attract confidence in its exchange rate. That's why I consider BitUSD a success until now, even if its stability was not perfect.

I have thought a bit about this list and got to the conclusion that the currently active stablecoins can be classified in two groups:

- Coins trying to adjust liquid supply to demand. In lower demand periods they activate a mechanism to reduce the liquid supply to reduce selling pressure. NuBits and the projects Seigniorage Shares, Basecoin and eMunie/Radix belong to this group.
- Coins where the stable coins in reality are contracts for difference (or similar "financial instruments") where a party (a speculator) takes the risk to lose a collateral, with the chance to earn profits in another asset (e.g. the BitShares currency or MakerDao Shares). This is the case of BitUSD, Dai and Havven, with Dai having a more complex stabilization mechanism.

For now it seems that the second group is more successful, as NuBits can be almost already regarded as a failed concept. The problem seems to be that it's difficult to really reduce supply - in the case of NuBits, the coins taken out of circulation were only "parked" and then could be re-inserted in the market. Basis/Basecoin (which seems to have partnered with Google) is, for me, a better intent as there is a real risk for "bond" buyers as bonds can expire if a low-demand period lasts too long. I'll observe this project closely.