To minimize moral hazard, central banks should operate as much as possible through general instruments not aimed at individual institutions. Open market operations fit this description, but so, too, can the discount window when it is structured to make credit available only to clearly solvent institutions in support of market functioning.
The Federal Reserve's reduction of the discount rate penalty by 50 basis points in August followed this model. It was intended not to help particular institutions but rather to open up a source of liquidity to the financial system to complement open market operations, which deal with a more limited set of counterparties and collateral.