Mental Set-up decides the fruit
Let us the take the cases of two such souls born in rich families. One soul may continue with the born mental set-up and in its case, the wealth is maintained or even grows by its actions. The growth of wealth is an encouragement given to the soul for its maintenance of good mental set-up. In the case of the second soul, the good mental set-up may change due to polluted atmosphere and hence, its actions give negative fruits and the wealth disappears. The actions of the both the souls may be one and the same, but different fruits are yielded due to different mentalities. Therefore, your mentality is the source of the fruit. Again, the ignorant people comment that the hard work of one soul multiplies its wealth and the same hard work of the other soul leads to the evaporation of even the existing wealth. This is the reason, why the hard work of one human being becomes fruitful and the same hard work of the other human being becomes waste.
The human being does not identify its own hidden mental set-up and blames its failure to be due to the irregularity of this systematic creation. This creation of God is the most perfect system and never goes wrong at any stage and at anytime. You can understand the mechanism of this creation-system if you recognize the basic concept, which is the preaching of God for the reformation of the human souls. Even the upper worlds like hell or heaven functions based on this fundamental concept only. All the punishments in the hell are only for the reformation of the soul and not due to any revenge. The teacher punishes the student for his or her welfare only and not due to any personnel vengeance.
Parents, who do not understand this basic concept, quarrel with the teacher for the punishments. The severe punishment given by the teacher indicates his or her concern about the welfare of the student. Intention of the action is very important. Similarly, the heaven contains some rewards of enjoyment in appreciation of the good deeds done by the soul. Therefore, the entire creation runs on the concept of the God as the divine preacher of the human beings. The human being here in this world or after death in the upper world is a constant student of Guru Datta only since the process of preaching is continuous here and there.