I don't know if I would say Genovese was bad. He was ruthless and cunning, surrounded himself with capable subordinates (Catena, Miranda, Lombardo) and groomed a future boss in Chin.

Perhaps he made some enemies along the way and was more than a little reckless, but that's part of what helped make the family the powerhouse of the New York mafia along with the Gambinos. When he went to prison the family was left in more than capable hands to the individuals mentioned above, setting the stage for the family's future secrecy and success at evading law enforcement that it still holds today.