It is narrated that the Prophet ﷺ said:

"He who supplicates for his brother behind his back (in his absence), the Angel commissioned (for carrying supplication to his Lord) says: Amen, and it is for you also."

This Hadith describes a reciprocal benefit system. When you ask for something good for another person without them knowing, an Angel ensures you receive the same outcome. This creates a logical incentive to support others, as their success becomes a direct pathway to your own. By removing the need for the other person to thank you, the focus remains entirely on the quality of the request and the certainty of the reward.