He feels that, although Youssef has come to West Ham to get first team action, the aim of the club is to then keep youngsters happy rather than let them regard Upton Park as simply a stepping stone.
"That would be the ultimate dream," he says, "as I am adamant that Manchester United's success - and they are the yardstick for everyone - is built on their youth policy, on their academy.
"If you look at their squad, over 50% of it have come through their own system in a two or three year band - seven, eight, nine players who have all grown up together.
"If we were to progress to a situation where at the start of the season we have the expectation of getting into a UEFA cup place, that will be built on what we produce ourselves in high numbers.
"It won't be built on buying success because we have never been able to do that, and we are certainly not in a position to do that now.
"If you can produce your own young players and bring in one or two young players, when you do enter the transfer market you don't have to spread yourself too thin.
"I look at Manchester United as a model in terms of producing young players and the way forward for us.
"That has always been the way, and the West Ham academy is well known throughout the British game, but we must keep finding our own young players and bringing them up to the standard of the Premiership."
Talking of his first summer signing, Glenn adds: "He is highly rated in his own country and although France didn't have a good World Cup, they were the world champions - and are still the European champions.
"They are in the top two or three nations in the world at the moment for producing players - and this particular young lad is highly rated in his own country.
"We are delighted to have secured his signature, and I would like to think he will start the season where Defoe did last season, where we will be able to start him on the bench, and see where he goes from there.
"If he can have the same sort of impact in the coming season then we will have signed an excellent player.
"From what I am told about him, and the reputation he has got in France with his club - he has always been in the national squads from the 15s to the 18s - he has real talent.
"It is not a concern that he has not played for the first team because in France, like Germany, Spain, and Italy, they don't push players into senior football before they are ready.
"We have really poor patience at times in this country, and it would be unnatural had he played in the first team already.
"In France they play them in their own age groups and the key thing for me is that he is always in the international squad of his level which suggests that he is one of the best 20 players of his own age group of a strong football nation.
"He sees West Ham as a club that gives young players an opportunity, and I think that is the big attraction.
"He looks at Defoe, Joe Cole, Michael Carrick, and knows about Frank Lampard and Rio Ferdinand in the recent past, and sees that this is a club that gives young players the chance to play Premiership football, and that is why he chose us.
"There were certainly other Premiership clubs that were chasing him, but we are the fortunate ones that have secured his signature."