It’s become normal in Wenxian’s household to think that his father’s behaviour and anger is always justified.
His father has high expectations of his mother. There’s no excuse for not performing to his standards, and there’s always punishment.
Wenxian’s reaction to seeing and hearing the consequences of his outburst has become normalised. If there’s broken crockery, it’s cleaned up. If father is about to explode in rage, hide.
Everything goes back to normal after that, and life goes on.
And Wenxian learns that when violence doesn’t shock anyone anymore, even himself.