You might say that, but you would be wrong. Parents of teens have been the most influential people in their lives up to them becoming teens. Part of the process into adulthood is to break away from that pattern, to explore and build connections outside the family sphere. That's why teens are the most vulnerable demographic for a lot of things -- their brains are in the process of rewiring themselves for more personal responsibility and less parental oversight. So they're actively seeking to avoid parental control, but haven't yet learned to correctly weigh and assess long-term effects of their decisions.