As emphasized by the information-theoretic approach to finance, a central function of banks is to screen and monitor borrowers, thereby overcoming information and incentive problems. By developing expertise in gathering relevant information, as well as by maintaining ongoing relationships with customers, banks and similar intermediaries develop "informational capital."
The widespread banking panics of the 1930s caused many banks to shut their doors; facing the risk of runs by depositors, even those who remained open were forced to constrain lending to keep their balance sheets as liquid as possible. Banks were thus prevented from making use of their informational capital in normal lending activities.