Since Carlo left Milan in 2009. His managerial tenures haven't exactly been long-lived.
Chelsea (Jul 1, 2009) until (May 22, 2011) sacked after 695 days
Paris SG (Jan 1, 2012) until (Jun 30, 2013) moved after 546 days
Madrid (Jul 1, 2013) until (May 25, 2015) sacked after 693 days
Bayern (Jul 1, 2016) until (Sep 28, 2017) sacked after 454 days
Napoli (Jul 1, 2018) until (Dec 10, 2019) sacked after 527 days
His median stay at a club since he left Milan is 546 days. To put that into perspective Carlo has been here at Everton for 208 days so far. Football doesn't stand still so Carlo needs to start delivering.