The distortionary effects of central bank direct lending on firm quality dynamics

Crises have cleansing effects: Low-quality firms face greater financial shortfalls and invest less than high-quality firms. Public liquidity support preserves the overall production capacity. However, by dampening the cleansing effects, it distorts the quality distribution and reduces the total productivity. The trade-off between quantity and quality determines the optimal size of intervention. The distortionary effects on quality are self-perpetuating: A downward bias in quality necessitates interventions of greater scales in future crises, implying further distortions. The distortions are also amplified by the expectations of liquidity support that motivate low-quality firms to overinvest pre-crisis. Finally, the size of optimal intervention is larger and the distortionary effects stronger in a low interest rate environment where the low yield on savings discourage firms from self-insurance against crises through internal liquidity accumulation