What supposed quality is presented in “yā wāshiyan ḥasunat fīnā isāʾatuhu”?

The Dialectical Method and Elegant Causal Attribution: Proof and Four Modes of Ḥusn al-Taʿlīl

• The informer’s report proving true
• The informer’s harmful action becoming beneficial
• The informer’s harm becoming greater
• The informer’s action necessarily increasing grief