even as a lay person I couldn't work out why quantative easing was being used.
If they question is why QE? then the answer appears to be, "ran out of other stuff to try."
If the question is whether QE is a good idea? (individually) it depends on your circumstances...
If you have debts, (arguably yes, QE is good, you are advantaged by inflation and QE will help drive inflation, Since the real term value of money is eroded over time)
If you have savings (arguable no, QE isn't good, since inflation outstrips interest rates, your money looses value faster than it appreciates.)
(most banks are paying interest at less than 2%, but the aim of QE is to drive inflation at 2%.)
If I have £50 right now, then I can buy 50 loaves of bread. (breakfast of toast for a year!)
in ten years inflation at 2% will have driven the cost of a loaf of bread to £1.20, but interest rates being 0.5% will have driven my money pile to £56.60
Now I can only afford 34 loaves of bread (no breakfasts after august)
the analogy of no breakfasts in winter is particularly good since it's pension savings that suffer the most from this policy of driving inflation above interest rates and thus devaluing savings, essentially taking away provisions set for the winter of our lives!
Making saving for the future, or at all not worthwhile means that you may as well spend what you have today, it feed nicely in to a consumer driven economy.