Karma is the universal law of cause and effect that maintains equilibrium in cosmic system. At any given moment of life the balance of cosmos must always come to zero, the negative must always be neutralized by positive all the time.
If negativity world over increases, so does positivity but at times the delicate balance of nature disturbs. It is in those moments’ advents an avatar, a messiah savior to save mankind from ills of today, re-establish Dharma (righteousness) and bring order in the society.
Karma does not necessarily mean tit for tat. Karma has a very deep-rooted meaning all the time acting as accountant general of cosmic system, keeping record of every single action indulged by living beings including human beings. In the domain of God nothing goes unnoticed.
If a thief indulges in theft unknown then law of karma catches with him sooner or later. Not necessarily in present life time! Karma can fructify any given moment of life. If we indulged in karma, the fruits of karma can become available now, a few days or months later even years or many manifestations after. This was so ordained by God so that intelligent human beings do not manipulate inscrutable laws of karma, backtrack them.
If we indulged in karma and for that matter any action whatsoever, it is not guaranteed that fruits of karma would become available immediately. Hence human beings must never wait for results of karma indulged. If our actions were good then results of karma would also be good. If we indulged in vice, bad karma then how could we expect a bright future ahead?
Every single indulgence of karma good or bad is our doing! If we suffered at the hands of fate or were lucky to win a lottery, everything resulted from karma indulged by us in past or previous lives. Why blame God Almighty for karma indulged by us?