#1 Last season's problems

If we look at the problems for Chelsea last season under Antonio Conte such as playing defensive football, not able to break down the opposition, conceding goals and losing as well, we can see that very little has changed this year.
Antonio Conte tried to play out from the back but Chelsea were often unable to do so and thus after some futile attempts they switched back to defensive football and won the FA Cup.
Though Chelsea are playing more attacking football this year, there are still elementary problems, such as the team being unable to break down the opposition and conceding goals all too often.
The style has changed but Chelsea are still unable to move the ball quickly around the opposition box and they just move the ball around, while in the process they have conceded goals as well.
The same was the problem under Antonio Conte, thus he needed Oliver Giroud to provide as a target man.
With the arrival of Sarri, it was expected that it would no longer be a problem but again, Chelsea are finding it difficult to break down the opposition. They have scored goals out of the weakness of their opponents rather than their own quality in most of the games.
As mentioned earlier, out of the Top 5 Premier League teams in the table Chelsea have faced the highest number of clear opportunities, only for the opposition not to take them. But against all the top opposition they have failed to keep a clean sheet.
In games against the likes of Everton, West Ham and BATE, where the opposition are tough to break, the Londoners have really struggled to find an opening, and as a result, they have only managed to win narrowly or they have dropped two points.
Thus despite Sarri ball, Chelsea, like last season, are failing to open up the opposition and on the defensive end, they are conceding goals as well, especially against the top opposition.