One of the problems that occurs is that managers are constantly changing. Remember they are managed by three different managers in one season so that the balance of the team is ruined. The selection of managers is also very poor, they don't seem to have better criteria. They seemed to be in a hurry. Another view is that they don't have a great No. 9 striker. Kai Havertz appeared unstable, Aubameyang was also rarely trusted by coaches. Let's wait for this season's transfer what Pochettino will do. Of course they have a lot of money ready to be used for shopping.
Chelsea is actually very good at recruiting star players, Chelsea's only fault is in the coaches and club management who like to change coaches. not a useless player, but a Chelsea coach who can't maximize the potential of players. It's like what you mentioned Aubameyang and Kai havertz who said they were useless for Chelsea. Look at the goals that have resulted in titles in the past... See also Mohammed Salah and KDB being thrown out of Chelsea, what will become of KDB now at Man city?
Pochettino includes the courage to train Chelsea, he is not worried about being fired via telephone like Tuchel who has presented the UCL. can he last long?