Louis Van Gaal has claimed Manchester United chief executive Ed Woodward knows "zero" about football.
Former United manager Van Gaal, 67, has blamed Woodward for the bulk of the club's problems since the Dutchman was sacked in 2016 after two years in charge.
Van Gaal, who has also had spells in charge of Ajax, Bayern Munich, Barcelona and Holland, told German magazine 11 Freunde: "At Bayern, the people in charge are football men. I always appreciated that.
"At Manchester United, on the other hand, Ed Woodward was installed as CEO - somebody with zero understanding of football who was previously an investment banker.
"It cannot be a good thing when a club is run solely from a commercially-driven perspective.
"I don't hold it against the club. They wanted Mourinho and he was on the market."
Van Gaal was heavily criticised during his two seasons at Old Trafford, when he guided United to fourth and fifth-placed finishes and won the FA Cup.
He was sacked two days after United beat Crystal Palace to lift the cup at Wembley in 2016 and replaced by Jose Mourinho.
"Appointing Mourinho was obviously interesting from a business point of view," Van Gaal added.
"He wins games. And for a club like United, the main thing is to win trophies.
"How they are won isn't the main priority, the English fans see it differently. They accept that the game is not all about attacking but it is also about defending.
"I always tried to defend high up the pitch, to be in the opposition's half and play the game there."