It's a calculation of: I'm losing X/year, it takes N years for them to die, and they want Y to go away now. Is X*N > Y? If yes, then I'll pay Y to them to go

It's a calculation of: I'm losing X/year, it takes N years for them to die, and they want Y to go away now. Is X*N > Y? If yes, then I'll pay Y to them to go away now.