Crows remember the faces of ‘dangerous humans,’ with the memories likely lasting for a bird’s lifetime.
Crows may scold people who threaten them, bringing in relatives and even strangers to mob the person.
The crows within mobs then indirectly learn about the person, so they too associate that individual’s face with danger and react accordingly.
God, why did you include crows in your plan for us? They are literally your greatest mistake, Lord. Amen.
(PS - Literally.)