The wise say that the fruit of sattvic action is pure and wholesome. The fruit of rajasic action is suffering. And the fruit of tamasic action is deeper ignorance.
When someone serves others without expecting anything in return, the inner reward is a quiet sense of peace. That is the sattvic fruit — clean, no strings attached. When someone works furiously for wealth or praise, even if they get what they wanted, worry and dissatisfaction follow close behind. That is the rajasic fruit. And when someone acts out of confusion or carelessness — skipping responsibilities, making choices out of inertia — they end up more lost than before. Darkness deepens. That is the tamasic fruit.
This is not a system of divine punishment. It is simply the nature of each guna working itself out. The quality of the seed determines the quality of the harvest.