Mauricio Pochettino got fired because he failed to meet up, it was a harsh decision from the Club's owner, Todd Boehly.
I think it is reasonable that Mauricio Pochettino has not been able to fulfill his promise because Chelsea did experience a serious decline in the previous season and the coach also needs time to be able to fulfill what is expected and since the time he took office as Chelsea coach he has improved Chelsea's performance and managed to finish better than the previous season, even though his contract at that time lasted 2 years if Todd Boehly had been more patient, Chelsea could have been in the top 3 in his second season, unfortunately the club was not that patient and they fired Pochettino at the end of the season.
Let's keep watching how Chelsea is going to end up this coming season, I have already said since the end of last season after firing Pochettino that Chelsea will regret why they sacked Pochettino, to be honest, I’m very disappointed with what Chelsea did, after everything he did to make the players played very well this season they still sacked him, if Chelsea allowed pochettino to continue as a manager of the team this season I believe that Chelsea is going to be in a better position in the premier league this season and also they can win a trophy this season but Chelsea didn’t understand that before sacking Pochettino.
Pochettino is very disappointed with Chelsea and we all can see it from his reaction even some players are very disappointed with Chelsea because after all they have gone through they have made a good team to play for another season that is when they sacked the coach, some players love Pochettino and we can see that at the end of last season, they played well as he wants, Chelsea is playing Europa conference league this season and some people think Chelsea can win the title, let see to the end because I will not be surprised if Chelsea ends up without any trophy this season again.