What goes around comes around. Blah blah blah blah blah.
The idea of karma presents itself as a method of inviting "good" into ones life by expelling "good" into the cosmic void. It takes cosmic forces to gather your "good" and "bad", but whatever plant you raise will present you with a yield or harvest of earned rewards.
If there truly was a way to gain a cosmic reward, for good or ill, it would present itself most assuredly in the immediate and horrible deaths of practically everybody on earth! Nearly everyone has done something that would cause the flow of "bad karma", inviting sure disaster.
Yet, planet-wide, the human population has not ceased to grow.
So much for ideas of karma and cosmic enlightenment!
I am become death, destroyer of worlds