If you want to retain the top talent you have to pay them. We chose not to. For a shirt period there was a lot of money made available to attract and retain youth talent, but when certain people left the club, the tap was switched off.
Losing genuine young talent like JJM and AGR is a big loss IMO. These are potential Shearers, Lallanas and Luke Shaws. If we are ever going to have a side that can thrive in the Prem again, we will need more than just a few young players getting into the first team, we will need one or two actual superstars to emerge.