why did Party leaders attack "over-idealism"? explain

"Over-Idealism" is the sense that a person too enthusiastic about any ideology, including the Communist, is libel to have too much individual expression. It really is Andrei’s “over-idealism” that sealed his fate. Not only was his strict adherence to doctrine worrying it also meant that he was unable to compromise. If the party wanted to change doctrine even slightly, "over -Idealism" was in the way.