#2 No plan B
Maurizio Sarri is famous for his unwavering belief in his style and in the players that best execute that style. When his team is winning, it is all good but his reluctance to change things up when he is losing or going through a poor run of form became a sticking point in his Napoli days and has reared its ugly head again at Chelsea.
The Italian tactician has blatantly refused to change his 4-3-3 tactics and has adopted this same formation in all Chelsea games this season. Even when losing, he refuses to make any sort of tactical alteration to the team. His substitutions are always 'like for like' and never alter team shape or tactic.
Olivier Giroud became a super sub in Arsenal because of the goals he scored as a result of his aerial prowess after coming off the bench. He is the second highest scoring substitute in the PL history. However, Sarri refuses to utilize such prowess and Chelsea keep playing tiki-taka even when Giroud is on the pitch. It remains plan A or nothing for Sarri's Chelsea.
Kante's role in the team has also been questioned after several defeats in which Kante in his usual defensive midfield role may have helped prevent. Kante, arguably the best defensive midfielder in Europe is playing higher up the pitch than usual.
These questions have seen Sarri uphold his resolve not to play Kante as the deepest lying midfielder and refuse to alter his formation to fit both Jorginho and Kante in the defensive midfield position as a 4-2-3-1 would do.
This has brought a considerable drop off in Kante's stats for interceptions, recoveries, and tackles for which he was top of the table in previous seasons. This season, Kante is on course to post his lowest stats for recoveries, interceptions, and tackles since he came to England.
Sarri seems too stubborn to change the formation or even alter the tactics. It seems to be either the 4-3-3 plan A or nothing for Sarri.