The Global Financial Crisis, triggered by the bursting of the US housing bubble, exposed the dangers of this wholly excessive credit creation.
Central banks have reacted to the growing deflationary threat, and widespread economic weakness, by setting monetary policy rates at all-time lows – putting the developed economies, effectively, on emergency life support. A deliberate side-effect of this policy, and of Quantitative Easing (QE), has been the boosting of asset prices generally, including bonds, equities, and property.
Courtesy of QE, many stock and bond markets are now both expensive and fraught with risk. Asset prices are in many cases uncomfortably high.