Lee told manutd.com: "We want the young lads on work-experience loans because we want them to experience a different type of football.
"We want to find out if they can play to a game-plan, which might be different to the one we'd ask them to play to in the Academy, with the Under-18s and Under-21s. It all builds into the repertoire of who can handle the pressure in senior football.
"That is also what non-league loans can do for goalkeepers specifically because, more broadly speaking, I think three of the four goalkeepers in the England squad currently started their careers in non-league."
Elyh Harrison spent last season on-loan with Chester, while Dermot Mee has had previous spells with Altrincham, Trafford, Runcorn Linnets and Witton Albion. Both keepers have been on the bench for United this season.
Lee added, "This season, Tom Wooster has been to Farsley, Tom Myles has been to Runcorn Linnets. They're going to really good football people who understand the game and can offer an opportunity and a chance for these lads to develop, which is invaluable to us.
"I think what people probably don't realise is where we're sending these goalkeepers. You know Antony Kay at Runcorn Linnets had almost 1,000 games in the Football League and his feedback was excellent. Chester and Farsley are the same. These are really good football people. They understand the game and can offer an opportunity and a chance for these lads to develop, which is invaluable for us.
"The record here is good and our job is to continue that. Our ultimate aim is to try to help give an opportunity to a goalkeeper to reach and play for our first team. But, if we can't achieve that, we want to help goalkeepers have professional careers up and down the league - from the Premier League to the non-league."