Why do bad things happen?

"In England artificial giants seem to have been a standing feature of the midsummer festival." James Frazier, The Golden Bough, pg 630

Why do bad things happen?  Well there are multiple things to look at.  First there is karma. 

Karma is like Newton's Second law.  For every action there is an equal and opposite reaction.  So if you are a jerk to someone, someone else is gonna be a jerk to you.  I believe that there is car karma.  If i leave a good parking spot, then i find another one thats as good or better.  Karma is one of the best things for evil people.  If a person robs you, something just as bad will happen to the robber.

Then there is luck.  Luck has 2 different definitions.  One is the superstitious kind of luck.  If you break a mirror, you will have bad luck for 7 years.  If you find a penny that is heads up, it is good luck.  If you have good luck, good things happen to you like finding money on the ground.  If you have bad luck, things like tripping in mud happen to you.  The other luck is just a description of an event that happens to you.  If you you trip down the stairs, you say you have bad luck.

Next is divine retribution.  Its when you do something bad, so your god disciplines you.  This can also be tied to the superstitious kind of bad luck.  In the metamorphosis of ovid, this is really easy to see.  When Actaen saw Diana, she transforms him into a horny beast to be eaten by his dogs.  This was an act of divine retribution.  This is apparently the most common explanation for why something bad happens to you because if you google "why do bad things happen to you?", a billion websites come up saying that its not God punishing you, its God strengthening you.