The Matildas then lost on penalties to Norway in the knockout stages with Slater adamant Australia fell well short of expectations.
“When you’re ranked six in the world, getting knocked out in the round of 16 is not good enough," Slater said on Fox Sports News.
"It’s quite simple, the World Cup was a fail. An absolute fail.
“A quarter-final for me is a pass mark but to be knocked out in the round of 16, it was a fail.
“If we’re going to hope for a medal at the next Olympics, we’re going to have to see a real change in - dare I say it - the culture of the Matildas and what surrounds them.
“Every time we hear the same thing, ‘We’ve learnt a lot, what about the next one?’ The World Cup is not a learning experience - you go to the World Cup to perform and to try and win it."
Though the side struggled to reach their full potential on the pitch, Slater believes off-field issues held the Matildas back in France.
Alen Stajcic's controversial sacking earlier in the year was a looming shadow over Australia's campaign, according to Slater.
"I think if we’re brutally honest and we cut to the bone and cut the crap, then there’s a lot that’s gone wrong," Slater said.
"The calamitous penalty shootout mirrored the whole campaign and I take the whole campaign as going back to what happening three months before the World Cup when they sacked Alen Stajcic for reasons that were given but weren’t clear.
"Everything was done, in my opinion, to upset that camp and the preparation was disastrous.
"As I say, I feel sorry for that group of players who have had to put up with all the political statements and all the selfish decisions by certain individuals and groups to come out and upset the relaxed camp for the Matildas to play their very best football."