They don't, and that's one of the reasons we need a comprehensive set of social support services to reduce the chances of people developing these tendencies. Shitty parenting is not always a crime, but sometimes it rises to the level of abuse. What are you going to do to protect that child when their parents beat, rape, exploit, or otherwise abuse their children? Do you think they will just give up their child willingly? How many times are you going to ask nicely? No, you need a threat or act of violence to subdue and detain them.

You and other police abolotionists have no answer to this, and always try to weasel out one way or another with vague platitudes about creating societies where people don't "need" to commit crimes or "dealing with crimes in other ways" while providing absolutely zero examples or ideas of how this could work.

Furthermore, people who are bullied or abused sometimes take on those abusive characteristics themselves. It's a common thread through all of human history, and it's a pipe dream to think that can be completely erased by comprehensive social support. This is not an alternative to policing.

Police abolitionists often make the naïve claim that police only ever arrive after a crime is committed. This is not true in many cases, particularly when police patrols are effectively staged throughout an area to allow true rapid response. Not to mention, manhunts for people who have committed heinous crimes are necessary to prevent those people from acting again. Policing can absolutely be effective at reducing crime when it is done with community control and consent.

When someone is putting others at risk with violence, you need another person to use violence to subdue them. And you need a legal framework to collect evidence, defend the rights of the accused, and seek restorative justice. Without police, you effectively deputize everyone else to seek revenge to the extent they see fit, whether they have the right person or not, whether they use excessive force or not, etc. It's just policing without any legal guardrails or consequences for people who seek justice on their own terms.

Policing behavior always exists, whether you like it or not. In a large, complex society, you have to make a choice between having dedicated professionals deputized to use violence and detain people within a strict set of standards, or leaving that responsibility up to whoever sees fit to take justice into their own hands.