In the cryptocurrency market there are no stable coins, all assets are very unpredictable and their price constantly fluctuates in different directions. Today she can make you rich and tomorrow she can make you poor like you've never been. Invest in the right assets
Unless there is a proper and constant verification and audit of the reserves.
Let's take the example of EURS (euro stablecoin). Each EURS on blockchain is backed by 1 fiat euro. If the price will go down and will be less than one euro, investors will buy and them come to STASIS (stablecoin issuer) and redeem it for 1 euro. So, there will be arbitrage and the price will be pushed backed to 1. In case the price will be more than 1 euro for an EURS token, investors will buy it from STASIS and then sell it to the market and make profit.
In order to assure investors and holders that each EURS is backed by one euro, they provide three streams of verification. You can check them our here:
https://stasis.net/transparency/