Adolescence is not simply a difficult phase, it is a deep transformation in which the brain and the sense of self are being reshaped, and understanding this helps a teen make sense of themselves and the world around them.
The part of the brain responsible for decision making and impulse control is still developing during these years, which explains why teens sometimes make quick, unweighed decisions.
Understanding this does not mean allowing everything, it means treating the teen as a person going through a genuine growth process, not simply as a difficult teenager to manage.
The first step is remembering that the brain is still developing during this stage, and that patience here is not weakness, it is understanding.