Why? It removes the the stocks from business and finance fundamentals, into more speculative (aka gambling) transactions that create huge BOOMS, and even largest BUSTS in the market, taking out peoples retirements, and financial security
One truism that I have always believed in, it is better overall for an investment to increase predictably @ 5%, then for it to Spike 20% then retract by 10%. Overall for the economy the person may end up with a higher gain with more volatility, but perception and human emotions would focus on the 10% loss, shaking confidence and causing other problems.
I am a "steady as she goes" person, I like clam waters... I do not like chaos which is what money printing causes