The intent of the COTS contracts was to procure launches for much less than the usual price by providing up-front payments in exchange for a block buy of future

The intent of the COTS contracts was to procure launches for much less than the usual price by providing up-front payments in exchange for a block buy of future launches. Seems to have worked great. Commercial companies sign contracts like that on occasion, when they don't like the prices from their current suppliers.