[klochner]

From the DAI site:

    > If the value of ether held as collateral is worth less than the amount 
    > of Dai it’s supposed to be backing, then Dai would not be worth one dollar 
    > and the system could collapse.

    > Maker combats this by liquidating CDPs and auctioning off the ether inside before the 
    > value of the ether is less than the amount of Dai it is backing.

Note combats not prevents, it will go to zero with probability 1 [0].

[0] https://en.wikipedia.org/wiki/Gambler%27s_ruin