Not just a paper loss...
The National NGO signed a large contract with an International NGO to implement a project.
The contract was in US dollars, and the full amount was transferred into the National NGO's bank account held in their national currency.
At the end of the project, the National NGO submitted accounts demonstrating how they had spent the full amount they had received in their national currency.
The International NGO's finance department calculated that, once converted back into US dollars, the National NGO had under spent by about ten thousand US dollars which they insisted were paid back.
The International NGO's coordinator found himself in an extraordinarily difficult position having to explain to his counterparts why they had to repay money they felt they had spent on the project.