Everton boss Roberto Martinez believes English football will always lag behind until they can find a way of bridging the gap between youth and first team football.
Managers such as Rafa Benitez, André Villas-Boas and Moyes have argued about the merits of implementing such a system in England.
"It is a sore subject," Martinez told the Liverpool Echo. "When you look around European football and you cannot do enough to develop young players.
"You come to the conclusion that the countries that develop the best young players are the ones who have a good games programme and the young players are allowed to play competitive football.
"That is something we are missing.
"Reserve football is very good for a young player for the first six months but after that I don't think it has the stimulation that a young player needs to develop.
"The Premier League and FA are putting in a lot of effort trying to find the right solution but it is very difficult to find the perfect environment for these youngsters to develop because they are missing competitive football at a crucial time.
"Loan football then becomes a need. The experiences of the players are away from the usual environment, away from your football club, and they can become a little bit of a gamble."