What is meant by teen driving 'inexperience' and 'risk-taking behavior'?

Question: What is meant by teen driving 'inexperience' and 'risk-taking behavior'?

Answer: All young drivers start out with very little knowledge or understanding of the complexities of driving a motor vehicle. Like any other skill, learning to drive well takes a lot of time. Technical ability, good judgment and experience all are needed to properly make the many continuous decisions, small and large, that add up to safe driving. By making it so easy to get a driver license­by literally handing teenagers the car keys without requiring an extended period of supervised practice-driving time­we are setting them up for the risk of making a fatal mistake.

Adolescent impulsiveness is a natural behavior, but it results in poor driving judgment and participation in high-risk behaviors such as speeding, inattention, drinking and driving, and not using a seat belt. Peer pressure also often encourages risk taking.