PSV Eindhoven chief Marcel Brands feels the step from the Eredivisie to the Premier League is becoming too great.
PSV have sold several players to Premier League clubs in recent years, while Ajax have seen Davy Klaassen struggle at Everton this season.
Brands told AD: "Part of the problem is players leave too soon.
"The Eredivisie is very close to dropping down a category.
"Defensive players find it easier in Italy than moving to England, where the pace is quicker."
He added: "Even with the Belgians, sometimes there were intermediate stages: Kevin De Bruyne at VfL Wolfsburg and Eden Hazard in Lille."