Global Market Perspective mentions non-self-liquidating debt as it shows this chart and says:
Total global debt has risen dramatically this year and [is expected] to exceed an eye-watering $277 trillion by the end of 2020, [which] will equate to around 365% of global Gross Domestic Product, up from 320% at the end of 2019.
[The] increase in private sector debt is not healthy, self-liquidating debt which, for example, would come from borrowing to invest in a new factory, the debt being paid off via the increased production. No, this is unhealthy, non-self-liquidating debt which is being added and the same is true for U.S. households binge on mortgage debt.