"I had expected financial institutions to start hoarding cash once negative interest rates have reached a certain level," Siekmann said in the radio program "Wirtschaft am Mittag". However, it would be very difficult to define this level as it depended on the cost of storing cash.
For Siekmann, the tendency of stockpiling cash is critical. If this tendency becomes stronger, the impact the ECB tries to achieve "would be taken ad absurdum", Siekmann said.
Deutschlandfunk: "Wirtschaft am Mittag" (2:00 bis 5:52 min)