Why did the court decide that stabbing five people after a man was besieged in Guangdong was not justifiable defense?

According to the circular, at 23: 50 on June 24th, 20 18, Ou contacted Zheng Mouyun to deal with the noise of the freezer next door (Zheng Jianfeng's younger brother). After Zheng Mouyun arrived at the scene, there was a contradiction between the two sides due to disagreement. At 0: 00/kloc-0: 00 the next day, Zheng Jianfeng passed the scene by motorcycle and met Ou et al. Conflicts between the two sides have become more intense and contradictions have increased. It is understood that Ou pushed Zheng Jianfeng first, and then there was a fight between the two sides. According to the on-site surveillance video, after Zheng Jianfeng parked his car at the scene, there was an altercation between the two sides. After that, Zheng Jianfeng was chased by about 10, and Zheng Jianfeng fled. What is more noteworthy is that in the crowd, a particularly conspicuous man in black was chasing after him with a long knife. In the trial verdict, on the European side, many people took part in the fight with wine bottles, wooden sticks and broadswords. In the process of escape, Zheng Jianfeng stabbed the other side with scissors, causing many injuries to the other side. After identification, the European side seriously injured 2 people and slightly injured 3 people. Then according to the first-instance judgment, Zheng Jianfeng did not belong to self-defense. So why doesn't Zheng Jianfeng's behavior constitute self-defense? First of all, we must understand what self-defense is. Self-defense is a defensive act to protect the personal and other rights of the public or others from ongoing illegal acts. Consequences caused by self-defense, such as killing the other side, shall not be criminally responsible. But self-defense cannot exceed the necessary limit. The condition that it must meet is the legitimate defense of 1 and it must be illegal infringement. It must be while the illegal infringement is going on. Self-defense cannot exceed a certain limit. In that case, what about Zheng Jianfeng? Get off before the motorcycle stops running? There was a conflict with Europe. The department arrived at the crime scene with equipment and took the initiative to stir up trouble. His behavior does not meet the time and conditions of self-defense. Therefore, his behavior does not belong to self-defense.