Mourinho led Inter Milan to a historic Treble last season, but Zaccheroni has slammed his tactical knowledge.
"He is someone who always needs to have an enemy, but then he gets offensive and that's not something I appreciate," Zac told Il Giornale newspaper.
"Tactically he's limited. I sent some Coaches to study him at Riscone in pre-season and in the evening they'd call to tell me there was precious little to learn.
"Now that he realised Inter would've won even without him, he has chosen to leave. President Massimo Moratti had always told me his dream Coach was Fabio Capello."