Among 46 names selected in a provisional squad for next month's Asian Cup were Jason Davidson and Josh Brillante, two players who have struggled for first-team football since joining West Bromwich Albion and Fiorentina respectively.
Despite Davidson in particular seemingly regressing since starting for Australia at the World Cup, Socceroos coach Postecoglou insisted the duo made the right call in heading to two of Europe's biggest leagues.
"It shows the challenge they have as footballers," he said.
"You've got to go test yourself, there's no point living in a fish bowl. That's the game we're in.
"I've got no complaints. They're two young men who want to test themselves against the best. There's no shame in that.
"The fact they haven't cracked it yet doesn't mean they've failed. Far from it.
"I'd much rather see our footballers back themselves, our footballers always do. And always will. But we're not going to tell people not to do that because of fear of failure. It's very early days to call it a failure. Hopefully over the next few years we'll see more and more of our players playing at the highest level."
Postecoglou justified the decision to include the likes of Rhys Williams and Josh Kennedy, both of whom are still recovering from long-term injuries, as a form of encouragement on their road back to fitness.
However, it remains unlikely either will feature in the final squad of 23, particularly with Kennedy, who will join Melbourne City in January, having no opportunity to play club football before the tournament.
"The information we have, in terms of the medical side of things, is that guys like that are in some form of rehab, but not totally out of the question," he said.
"There's a challenge - the fact they haven't played in quite a while has to be taken into account."
Half of the provisional 46-man group will be cut on December 30 by Postecoglou, who indicated the majority of his final squad has already been decided.
"If everyone's fit and well and everyone's in good condition, I'm pretty settled on the kind of squad we're going to have," he said.
"Having said that, we just want to make sure we're covering all bases."
