http://www.forbes.com/sites/janetst...-is-the-prime-directive-ethical/#31a6e1b1642b
Ethnocentrism vs Cultural Relativity
When analyzing this, we can see the three stage process quite clearly. The first stage is the separation stage. This can be either when the boys are taken to kill their lion (according to the myths), cloaked and painted, and then taken into the tent. The second stage is the transition stage. This can be seen as what the boy goes through when he is inside that tent. He is circumcised, and this marks his transition from boy to man. It can also be said that the 4-8 months of having to wear black clothes could be also part of this transition; it can mark the spiritual transition of the boy into man. The third and final stage is the incorporation stage, where the boys are re-admitted into society as warriors. These warriors have a different job to do than the boys (they can now be seen as protectors of the village), and they are also ranked higher on a social scale (are more important, in other words).
This usually begins at age 12. But the boys certainly do not go on a lion hunt completely unprepared. They most certainly would have been party to a hunt prior to age 12. In fact groups of young boys, aged 5-12 will take smaller game honing their skills in preparation for their initiation day when they will or would have been required to take down a lion. (Lion hunting has been banned in the country referenced)
Not sure how many of them grow up to be "psychos".