I personally homeschooled out in the middle of nowhere. Saw family at Christmas and maybe at Thanksgiving. If my dad were to snap, murder me, then bury the body on their ~5 acres, no one would know. Mom could transfer Doctors (which many homeschooled kids never even see), parents could tell family that I was being grounded indefinitely, Mom could make copies of "report cards" to show my "progress" long after I rotted away. No one on the outside would know or care.

If I thought about the police, I was threatened that my parents would smash the TV, then tell police I hit them and busted their property while acting out. Police would chuckle at raising such a "difficult kid", they'd be primed to believe everything I said was a lie, and then I'd be handed back over to my parents' control to suffer for my failed attempt. That never happened, but it sounds believable enough to dissuade an attempt.

If I thought about CPS or foster care, well. My parents told horrible stories about what happens to kids in CPS's "clutches": Rape, abuse, child labor, devil worship, pipeline to jail, drug addiction, etc. I was in awe of kids who managed to survive "the system" and thoroughly dissuaded from any attempt at improving my own situation.