Surely you came across the old & trusted folkerism "The One That Got Away".
So many historical examples; makes one cry.
Just here on our doorstep Police Elite unit was urged in 2017 to arrest the Bourke Street madman.
Elite police unit refused to help arrest Gargasoulas before massacre
This is the real-life example of the "The One That Got Away" and the so called 'elite unit' has blood on its hands.
Hardly anyone will subscribe to such mentality
"What's the point of killing the Killer; another one even worse will replace him".
It's like the Weeds in the Garden; must keep weeding them out.