Chelsea also made a hasty decision in my opinion, especially about selling important players. Mason Mount was one of the most important players for Chelsea in recent seasons, Kai Havertz too, but they sold him to Manchester United and Arsenal instead. Admittedly I was pleased when Manchester United managed to sign Mason Mount, but it was a big loss for Pochettino who was hoping for more good depth to his squad.
I will not be completely sure Pochettino will succeed in building Chelsea as quickly as expected, that's because he and some players need adaptation. Next season it is clear that there will be many opportunities for players like Mykhailo Mudryk and several other new players, so of course they need time and adjustments to the strategy from their new coach.
Mason Mount is important player for Chelsea but faced difficult get regular position last season and looks not happy stay with Chelsea until his contract over, seems logic when loss position as main player move to other team who guarantee with more minutes playing is the best choose for Mount. Kai Havertz seems the same thing happen for him, including not in scheme under Pochettino has potential for him spent more in the bench and joining with Arsenal will make difference to get more minutes playing.
But still unbelievable with Chelsea transfer activities, they have sell many important players without get balance between player out or in and I don't optimist with Chelsea has promising performance in this season and back to the top fourth standing positon.