Cesare Prandelli has questioned the way Valencia is run after resigning as head coach after just three months in charge.
Valencia picked up just six points in 10 La Liga games under Prandelli, and their sporting director Jesus Garcia Pitarch has said the former Italy coach walked out after being told he could have only one of the five experienced players he had requested in January.
Garcia Pitarch told Superdeporte: "The price is high for the level of players he wanted to sign and that we all would like to sign, and we spoke that perhaps one could come but not five. He said if they didn't arrive as soon as possible he could leave that same afternoon."
Prandelli held a news conference to explain his decision to leave 17th-placed Valencia at which he read out a statement, taking no questions from the reporters in attendance.
"I leave here with a lot of emotions, and feeling very sad," the 59-year-old said. "A dream has come to an end. I knew that I had accepted a difficult challenge, but I came here convinced I could help Valencia out of their difficulties.
"Sadly, it didn't happen that way."
Prandelli went on to criticise the way the club is being run and said had expected to welcome Simone Zaza into training at the end of the year, but was left disappointed as the forward did not arrive.
"This club is made up of respectable people, but they are obsessed with numbers," he said. "Football is about passion and feeling and if you don't have these ingredients, it's hard to go anywhere. I wanted to open training up to the fans, but they said it was not possible.
"I tried to talk to the press, but they had a blacklist. I collaborated with the club in silence. They told me from Singapore that they would have strengthened the club in January. [Owner] Peter Lim agreed with me and he had told the sporting director to focus all of his efforts on signing Zaza, who was meant to arrive here on Dec. 27, after the holidays.
"He's a player who has character and we didn't have a player like him in the squad, without forgetting that he is just the kind of player that the fans want to see. On [Dec. 29], Zaza still wasn't here, but that is not everything.
"The club asked me to pick between a forward and a midfielder, forgetting all about the four [signings] they had promised me."
Prandelli's three-month spell as Valencia coach was only slightly longer than his 16-game spell at Galatasaray after leaving Italy's national side following their group-stage elimination from the 2014 World Cup.
Former Valencia player Voro Gonzalez will step in for the second time this season as interim coach and will guide the side when Valencia host Celta Vigo on Tuesday in the Copa del Rey round-of-16 first leg.