What happened to this??

What happened to this??

Observation - What happened to this?? - UK and Ireland. Description: This poor thing was looking very battered and torn, it lacked the vibrant colour that I usually see in these beautiful butterflies. It looked very anaemic. Why is this this ?

This poor thing was looking very battered and torn, it lacked the vibrant colour that I usually see in these beautiful butterflies. It looked very anaemic. Why is this this ?