Southampton are a good example but even they have lost their potential 'stars' at 14, 15, 16.
What they do well is when the rest of their players get to 18/19, if they are good enough they are given a proper chance, thats what Albion dont do very well. Wan Bissaka is now 21, but up until a couple of years ago Palace were playing him as a winger and had real doubts if he was going to make it there, he moved to full back and two and half years later is moving for £50m quid.
The big boys buying players at 14, 15, 16 are just buying potential, say Louis Barry goes to PSG, there will be another 4 or 5 like him in that squad, 1 of them will probably make it as a top top player but for the sake of a few million investment now with compensation, wages, etc for 4 or 5 potential stars, the 1 player who does make it as a top player saves them millions and millions down the line, all they are doing is having a safety net, the big clubs sign the top potential youngsters working roughly on the ratio above.
There is a big difference in physicality and mentality between 16 and 18, i think the ratio of lads who get taken on full time scholarships to those making a career out of professional football is still in the single percentage, yet everyone of those lads who are taken on have something or some potential at that age, the two years between 16 and 18 is massive though.
You now and again get a lad who just seems to be almost a man in a boys body and is ready to play first team at 16/17, from the academy games i have seen Morgan Rogers looks the one who could do that.
As said previous what we have to do is when these lads sign professional after their scholarships, is have a clear plan, like Southampton do, if your good enough you get the chance, if your not you go out on loan, instead at Albion we have players like Leko and Field who broke through three seasons ago and are not really much further along in their personal careers as they were then, they havent played regular for us, not been out on loan (Leko had a few months somewhere but thats it) thats what has to change, if you dont think they are good enough, then sell them for our sakes and theirs.