Question: reasons why gryffindor is the worst?
Answer: They're arrogant. ...  They're judgemental. ...  They always think they know best. ...  Loyalty clearly doesn't have a definition in the Gryffindor house. ...  The teachers, Dumbledore in particular, favour them. ...  They pretend to be goody two-shoes. ...  But they actually break the rules ALL THE TIME and get away with it.