Silva has now scored four goals in five appearances for Anderlecht after an impressive start to his season-long loan.
But Lage admits it was a brave move to allow Silva to leave, after Wolves splashed £35million to sign him two years ago.
"We need to take brave decisions, that's why we are in this position," Lage said.
"Ruben Vinagre was here, he went to Sporting on-loan and then they bought him, and now he's been loaned to Everton. It's hard to take these decisions.
"The target is to take the best from the players. Tell me a good player at age 21, 22 or 23 that you can buy for £10million or £15million? Sometimes you need to pay £50million or £60million.
"We need to find them when they are young, bring them in and give them time to grow up.
"If they are improving but need more time, lets find a different place for them to grow up. It's happened with Fabio and now he's growing up in another place, and it happened with Morgan.
"He had half a season at Swansea, came back and didn't play much, had a full year at Sheffield United and now at 22-years-old he's a top player."
Gibbs-White has returned to Wolves as a first team starter and a player that is interesting other clubs.
Lage hopes that Silva's year in Belgium will mean he returns ready for the Wolves first team.
"That was the main point when we started pre-season and I had a chat with Fabio," he added.
"After two years, he came with big expectations and ambitions. He played but didn't play the time he wants because everyone wants to play.
"Last year he didn't score a goal but now he is scoring. It's about the opportunity to find the best space to continue to grow up, improve, be happy and score goals.
"Sometimes a different environment away from his team-mates (can help). He went but signed a new contract, so he's still our player and we are happy.
"I want to look at the end of the season and see the same as what happened with Morgan. He goes, grows up and now he can be an important player for the team and me. That's what we want from Fabio."