Vito though was making a mistake as he gave jobs like the other Dons did in Sicily to people who might not be qualified for them. Dr. Taza for instance is a doctor no one willingly would go to. Don Corleone wanted friendship more than giving people important jobs that they need to be qualified for. Michael realized that eventually this could spread and he does what he thinks is right and he will hire the men who he feels qualified for jobs rather than just making friends.