The government specializes in obfuscating things so that the average citizen really doesn't know what is going on, for the purpose of such, is to take what could be explained in a rather conventional way, and instead make it somewhat confusing and to therefore control the spin in favor of the orthodox government viewpoint. The financial crisis of 2007-2009, necessitated drastic action, yet, the end result was for the government to work with the favored banks of America so as to reduce, in theory, the toxicity of their assets as well as to jettison growth in America, therefore, the geniuses behind the government's monetary policy came up with the concept of the central bank purchasing a total of $3.5 trillion dollars of government securities which lowered interest rates for a historically long period while also increasing the money supply, in the belief that by doing so, banks now being more liquid, would therefore lend more money, thereby increasing business activity, which would "goose" GDP growth, as well as giving banks increased liquidity by papering over zombie and mismanaged debt carried on their books.
The government likes to say that quantitative easing is not the printing of money, but essentially in any real conventional way of analyzing such, it most certainly is, for the buying of government bonds, by the central banks, creates money that did not previously exist, and that is the printing of new money. This new money thereby suppresses interest rates mainly because there is even more money to loan, though, there aren't really any new viable places that did not exist before, to loan that money for or to. So that, not surprisingly, since money has been created and put into the hands of the central bank consortium, those at those banks, aren’t really interested so much in loaning money out, which has attendant risks associated with it, but rather would prefer to passively invest it in either low risk securities or equities, made far easier by the fact that the cost of borrowing this money is so low.
Though America has ended its quantitative easing, and has made promises of paying off the government securities so borrowed in a systemic and controlled way, the problem that will be created is that when the money supply is increasing, equity markets and businesses typically do quite well, especially when interest rates, or the cost of money, are correspondingly either low or quiescent. Therefore, when that money is being paid back, it compels industries, equity investors, and individuals, to reduce their leveraged bets and borrowed money considerably, not only because interest rates or the cost of money is going up, but also because nobody wants to be the last person holding onto the bag, especially when over the previous decade, good money has already been banked and made.
Though the experts like to state that quantitative easing is not actually the printing of money, if and when that $3.5 trillion dollars is actually paid back, this will demonstrate the truth of that proposition, for in actuality, this government when given the choice and mandate to make systemic change to replace or correct our financial institutions that were deemed to be "too big to fail", decided instead to throw good money to paper over bad problems, of which, if these bad problems, such as zombie debts, precarious leverage, and non-performing loans have not been somehow materially improved substantially, will show that when that money is repaid, the financial truth will be re-exposed, in which bad recessionary conditions, a stock market collapse, and the awesome tottering of our financial institutions, whose fiscal house has only been papered over will threaten to collapse.