Allegri-Juve like Sacchi-Milan: when players are prioritised
The main reason behind the sacking of Allegri comes down to his ambitions as a coach. He reportedly wanted to change many players ahead of the new season, looking to spark a revolution in order to win the Champions League. However, the club opted to go with the players, thus letting Allegri go while continuing their project with a different manager.
At AC Milan in the early 90s, the same situation took place as the Rossoneri opted for the players rather than Sacchi, who wanted a revolution as well. Van Basten reportedly told Berlusconi 'It is either me or him', referring to Sacchi of course.