There is so much cash out there as a result of multiple QEs that it is concerning that the global economy isn't stronger than it is.  Even Warren Buffett confesses he's looking for ways to deploy cash.

See Japan from about 1990 onward  for an example of where we really are without the boatloads of extra cash floating around.   QE made a lot of sense to avoid the 1929 scenario, to a point -- it may have gone a bit too far and now is extremely tricky to rein in.   

What we have now doesn't make a lot of sense in the economy.   It's a bit like walking into a fair-sized town in the desert expecting to find food and drink, only to discover that there is no food, no water, and not much of substance, and all the buildings are false fronts from the abandoned movie set of a film shot decades ago.   How else is it possible to explain the absurdity of Snapchat's IPO?