Cassano is unimpressed by Motta's first season in charge, particularly after their home humiliation at the hands of Atalanta.
He said on Viva en Futbol: "At this moment he is unthinkable, he cannot have the status to coach Juventus. Given that the disaster has been made, I would tell (sports director Cristiano) Giuntoli that, going back, I would never have sent (Max) Allegri away.
"As players, the Bianconeri are much stronger than Atalanta, whose players have become phenomenal thanks to (Gian Piero) Gasperini, who is a genius. When they go to change the coach, we also need to give Giuntoli a dressing down, who has put his face on the players he has taken and also on the choice to send Allegri away."
Cassano continues: "I don't give a damn about him, I don't talk to him anymore, I'm not crazy about him and he doesn't give you anything in terms of football, but going back, given that in 40 years I've never seen fans abandon the stadium before the final whistle and not value anyone... We've gone beyond Haifa.
"Now he should explain to us why he sent Allegri away to take someone who is doing much, much worse. In one way or another he takes you to fourth place, instead now they are in terrible difficulty, without a game, with everyone devalued.
"The thing that left me stunned was the choice to put (Teun) Koopmeiners on the right wing: he's already struggling in midfield now..."
Finally, he concluded: "Thiago Motta is a very good guy, he's got two balls, but, reluctantly, I have to backtrack and say that they probably made a mistake in sending Allegri away."