That is the view of his brother Mustafa, who explains:
"He has spent four years at the centre de formation - the training centre - at Auxerre, and that has helped produce a generation of champions of the world and Europe.
"Since 1994 it has had a good reputation and has brought top class players through, and everyone knows Youssef's name in France.
"It is a big training centre that has produced players like Djibril Cisse and Steve Marlet, but the fact that he has not played for the first team is just because of the system there - you have to wait, even if you are the best.
"Along with Lyons, it is the best centre in the country, and he had the opportunity to stay in France, but it was more interesting for him to come to France."
Youssef, who finalised his move to Upton Park on Monday, chose the Hammers above the many other clubs - both here and abroad - because of Glenn Roeder, says Mustafa.
"He has a lot of respect for Glenn, and it is that, above all, that determined the decision to come to West Ham.
"Because of Glenn, it was obvious that West Ham was the best option of the many choices he had, and he is very happy to be here.
"It is a challenge for him to be able to play in England, but his style perfectly suits the game here - and he already knew that two years ago.
Youssef only knows the French players at the club - Sebastien Schemmel, Laurent Courtois, and of course, Fredi Kanoute.
Mustafa thinks that Youssef would be a perfect foil for Fredi if that opportunity arises, and explains:
"Youssef is a modern striker, the sort who likes to get forward quickly - and I think Fredi would be a complementary figure, one who could make space for him to use his speed.
"Along with Cisse, he was the fastest player at Auxerre - maybe slower, but only by 1/100th of a second!
"I think West Ham is just the club he needs."