I think Gotti was worse, Scarfo at least didn't order his capos to regularly meet right under the FBI's nose. Also Scarfo was too violent, but in my opinion that's not as damaging to the organization as being flamboyant, many very violent bosses were successful, like Genovese or Anastasia.

Willie Marfeo to Henry Tameleo:

1) "You people want a loaf of bread and you throw the crumbs back. Well, fuck you. I ain't closing down."

2) "Get out of here, old man. Go tell Raymond to go shit in his hat. We're not giving you anything."