What is true for young men with a driving licence?
It is in fact true that young men are more careful when they have just gotten their driving licence compared to when they have had their driving licence for a year, and not the opposite. (Driving Licence Book, 19th Edition, page 183)
In the beginning they are still unaccustomed to driving and try to get into a routine. When they get used to driving, they start taking greater risks and challenging their boundaries.