Manchester United head of academy Nick Cox insists all their loan arrangements this season have been positive.
"I don't think there's such a thing as a failed loan," he told the Manchester Evening News.
"There's only experiences. So if a boy goes out on loan and doesn't play, that can be just as wonderful an experience for your long-term development as playing every week.
"But you've got to get the balance right. You can't have a boy not playing for long periods of time."
On the decisions to recall the quartet and find three of the players new clubs in January (all except Kovar), Cox admits United's contacts book plays a big part. Clubs down the football league and around Europe can make great use of the strong talent pool coming from Old Trafford.
"You sometimes have to reconsider a loan period, move boys around and consider where they're at," Cox says.
"That's a lot of communication between the staff internally, the player and the network of clubs we have strong relationships with.
"We made a decision this year to be really proactive with getting boys out on loan. We looked at the boys we had, the competitions available to us and decided 'yeah maybe it's time to be brave'.
"It would have been easy to keep the boys back in the building and win games every week but that's not what we're here for.
"We put boys out and the knock-on affect is that you're seeing our Under-23s with young players in, you'll see our Under-18s with young players in. Because that's the right thing for the individuals."