But what we don't know in Pochettino's contract is what, did he have a promise that he could bring Chelsea to the top 3 last season and when he couldn't achieve it Pochettino was contractually immediately released because he couldn't keep his promise.
I don't think it's possible to get this Chelsea squad into the top 3 in 1 season. Chelsea's situation was very shaky. Performance was unstable. However, Pochettino did his best to strengthen the squad and bring stability to the performance. We saw an improvement in Chelsea's performance towards the end of the season. However, Chelsea could not qualify for the Champions League or the Europa League. Chelsea management might not have sacked Pochettino if Chelsea had qualified for the Europa League.
Whether or not Chelsea's new Enco will be able to strengthen this team is uncertain. But I would say Chelsea management should let the coach work independently and not change the coach in atleast 2 seasons. Changing the coach so quickly has such a bad effect on the performance of the players.