The common phrase, ‘snitches get stitches and end up in ditches,’ is currently used in schoolyards, though it originally came from urban communities regarding illegal activities. They would say it to someone they considered potential police informants, as a form of intimidation for their own self-serving reasons. Since then it has been used in jails, gangs, schoolyards, comedy, and anywhere else culture has an effect.
I first heard the phrase as a young boy, and took it to mean if I tattle-tale’d, the person who said it wanted to fight me; like in general. But the concept didn’t fully become clear to me until later on. The type of honor culture surrounding the phrase is as old as humanity itself. It’s tribal in nature, being used as an almost test of trust. If one kid threatens another with the saying, and the kid says nothing or even lies, it boosts their reputation to that other kid.
It’s difficult to place this saying solely in the ‘bad’ category on its criminal origins alone because it does do something good in principle with children: it teaches them how to make friends. If the crime is harmless, and no authority figure discovers what happened, a bond between the two is formed. It really boils down to particular situations and the consequences, short or long term, that may come. Decisions are like living in a burning house where you die a thousand small deaths before the fire kills you, so make the small deaths worth it.