73. About loan waiver in Islam 

The rich are required to help the needy and others by giving out their excess wealth to people such as loans or charity. But some Muslims without any qualms charge interest for the money they lend out to the needy. 

Charity made with the intention of pleasing Allah alone is accepted by Him. But Allah relaxes rules when it comes to people giving out loans. When the money given as loan shows no signs of return and waived off, it is deemed as charity accepted by God is what this verse (2:280) conveys.

Though while lending we did not have the intention of charity in our mind, Allah blesses us with a concession of benefits by treating the unreturned money as charity.

Similarly, a person who is duty bound to pay zakat can also treat the money not returned as zakat paid by him.