They are thinking too concretely to understand the world. David
Elkind think this is because the teenager goes to the stage of formal
operation of thinking at age 12 and they learn to be more critical about
the things that surround them, this kind of thinking leads them to be
very concrete in their way of seeing the world and consider more their defects and those of the people around them, this is why they tend to be rebels.
I hope my answer can help you.