It all boils down to street cred. He wanted to ‘up’ his street cred and instigating a fight and stabbing would do exactly what he wanted so badly.
He would have gotten praise and adulation from his homeys and they would have reinforced his self-entitlement.
When he was captured he essentially bragged that HE WAS THE ONE THEY WERE LOOKING FOR, and said “I DID IT!”
Then he inquired as to the condition of the boy he stabbed, thinking that he was only wounded, but the cops wouldn’t tell him anything.
He thought that if he was only wounded he would just get off with a slap on the wrist because of his age.
And then he would be Mr. Badass among his worthless ‘friends’ and homeys. Most of whom will probably be joining him in prison over the next few years.
What a class reunion!....................
I suspect he also wanted to be a gang member. One of Nancy Pelosi’s BFF’s.