Loans can be beneficial for some players, less so for others. I get what
@Eggs is saying because it does sometimes seem like everyone wants every single young player to go out on loan as soon as possible and there's very little evidence to suggest it's a good idea. I wouldn't really class Holgate in the same bracket as the majority of prospects now, when he went out he was 22 and had loads of first team experience already. I don't think that was a development loan really, they just didn't fancy him and so let him go. I think they'd have happily sold him if the opportunity was there.
The main issue with loans is knowing where to pitch them. Everyone always wants players to go to a club that's at the top of the Championship but I'm not sure why. You need to get them a club that will do right by them, at a level that will be a challenge but also not beyond them. In some cases you'll want them to be local so it's not too much upheaval (particularly for someone like Branthwaite who's already had one big move in the last 12 months), in others you might want to get them away from the area for one reason or another. It's not easy to find clubs who want your player and tick all those boxes. I think a lot of people forget that when we loan someone out, our objective and that of the loaning club are pretty much the exact opposite of eachother. We want a player to learn and develop, they want someone who will make an instant difference. We want Simms to develop his all round game but if he goes on loan in January the chances are the team he goes to will have no desire to encourage him to do that, because it has no benefit to them. They'll likely just want him to score like he does for our junior sides, and so all the work he puts in with our coaches just stops for 6 months while he's used as a sub to throw on when his team's looking for a late goal.