>>The essence of debt deflation is that when prices and wages fall with the price level, but the nominal size of debts and interest payments are fixed, then borrowers face increasing pressure on their ability to repay. This in turn leads to a leap in loan defaults, which in turn can cause bank insolvencies.
The commonly assumed danger of debt deflation is that it can lead to a deflationary spiral, as defaulted debts lead to write-downs by banks and other creditors, which constitute a reduction in the overall volume of money and credit in the economy, which spurs further price and debt deflation in a vicious cycle.<<
https://www.investopedia.com/terms/d/debtdeflation.asp