"When you start getting players being sent off all the time and heads go down, there is a point where I felt I had to do something drastic to turn this thing around," said Levy.
"I think it was plain to see that some of the players weren't performing as well as you'd expect them to perform."
Ramos has received sympathy for working in the continental structure where sporting director Damien Comolli scouted and recruited players, a system scrapped following the appointment of Harry Redknapp.
Comolli's transfer record was poor but Levy insisted that Ramos would have the final say on signings.
"There has never been a player signed or sold by the club that the coach has not supported," Levy said. "They are ultimately the coach's decision.
"In the case of Dimitar Berbatov, at the end of the transfer window when we weren't successful in bringing in an experienced striker, it was the coach who decided to let Dimitar go even though we didn't have a replacement.
"Juande managed the team and his advice was that he didn't want a player that didn't want to be in his squad. He thought it would be detrimental to the team as a whole. I backed his advice."