The Asian Child was a right little bugger. Pretty much everything bad that happens to the Eighth Doctor right after he regenerates is Chang's fault. He got Seven shot and stole his shit. He abandoned Eight at a hospital. He opened the Eye of Harmony for the Master. He stole an ambulance. He took the Doctor's pouches of gold dust that the Doctor just has for some reason. The Master snaps his neck, which is pretty much exactly what the shit deserves, but then the TARDIS brings him back to life for some raisin. The Doctor just wants the kid gone and bribes him with gold so that he'll never bother him again.
Note: Chang was mugged and killed on his way back to his home planet.Edit
Mental Limitations Edit
Chang is dumb. Even for a street urchin from San Francisco in 2000. He believes a guy who dresses like the goddamn Terminator. The Master hypnotizes him for like five seconds, but he's totally cool with everything else. Also, his friends get shot and killed right in front of him, but it never seems to bother him. Maybe he's just too stupid to understand what death means. He stole an ambulance. People probably died because he was out playing real life GTA with his new evil buddy chasing a mental patient and the woman having a breakdown because of him on a motorcycle.