Jose Mourinho has focused on Manchester United owner Sir Jim Ratcliffe's handling of the club in a broad interview.
Mourinho, 62, revealed everything when he sat down to speak with Portuguese TV channel channel 11.
The Portuguese coach, who is currently in charge of the Turkish side Fenerbahce, managed the Red Devils from 2016 to 2018 – during which time he won the Europa League and United led to their previous Premier League finish of Second.
Now he has cited the departure of the former CEO David Gill of the club, who left them in 2013 after 16 years.
Mourinho said: 'There is a critical moment in that club, not only with the departure of Sir Alex, but also with David Gill's. David Moyes came in, but when my Netflix documentary comes out, the story is told.
'I arrive later and when I arrive, I arrive at a club that still goes through that period. We have won several things, we finished second in the competition. I still say that I don't understand clubs that are being punished with financial fair play and pay [in cash].
“I think they have to pay points. Manchester City was punished and legally we should have won the competition. But it wasn't enough for me to have stability, continuity.
“Today I think that with the change in ownership at the club, with an owner who does not have much experience in football but rather in sport '.
The Portuguese manager then discussed the implementation of his fellow countryman in the current coach Ruben Amorim of United.
Mourinho offered Amorim the chance to visit the Carrington Training Ground of the club when he did a coaching internship in 2018.
However, that earlier experience has not translated into success on the field for the younger Portuguese coach so far.
Amorim had moved to Old Trafford halfway through last season after he had chosen to leave Sporting CP, a difficult first campaign at the helm.
Under his stewardship, United registered their worst Premier League finish of the 15th and will not play in Europe next season after he has lost the Europa League final to Tottenham in May.
However, Amorim will hope that next season will yield better results after he has protected Matheus Cunha from Wolves and Bryan Mbeumo from Brentford in an attempt to strengthen the attacking firepower.
Mourinho added: 'What happened to Ruben, from the manager of the worst Manchester United in Premier League history to having continuity and trust to continue and be Ruben Amorim, is a sign that much has to change.
'With that stability … We all agree that he is a manager. With a great potential and personality. I think he has an incredible potential to do a great job. '