The "ratchet effect" of central bank liquidity

We have only one example of a central bank that has tried to reduce the size of its balance sheet after using quantitative easing: the Federal Reserve in 2018 and in early 2019. However, it very rapidly had to put an end to this policy of balance sheet reduction and asset disposals. We look at what caused this liquidity contraction policy to be interrupted. The reasons were: Falling financial markets (equities, corporate bonds); Declining corporate and housing investment due to the rise in long-term interest rates; The dollar’s appreciation. This reinforces our view that the bonds bought by central banks will never be resold and will be rolled over on maturity, and therefore that the bonds held by central banks are indeed "zero-coupon perpetuities".