As described in BETH's token page, BETH serves as a representation of burnt ETH. WORM is, then, a representation of redeemed BETH because it can be obtained from an effective internal market by submitting a quantity of BETH. In this way, it obtains soft backing by the burnt ETH associated with the totality of WORM mining, establishing a correlation of WORM's inherent value with the total value spent to mine it.