The Ireland captain believes Joe Schmidt’s men must seize the “reality check” of turning last term’s Grand Slam into a third-place finish this year.
“When Joe first came in the big question was ‘how do we perceive ourselves?’, and the big answer was ‘inconsistent’,” said Best.
“And what we’ve worked hard to do is to prepare the same whoever we play and whatever we do.
“That’s how it’s always been under Joe and we certainly won’t go away from that now.
“It sometimes takes a reality check, and finishing third was bitterly disappointing.
“So coming in at the start of this pre-season everyone is as hungry as I have ever seen them.
“We’ve had a group of players that want to prove that the 2019 Six Nations was the blip, not 2018.”
Ireland host Italy at the Aviva Stadium on Saturday to kick-start their build-up to the World Cup in Japan.
Schmidt’s side will launch their World Cup bid by taking on Scotland on September 22, with confidence still riding high among Irish fans of a best-ever tournament.
The long-serving Ulster hooker will be 37 by the time the tournament kicks off but admitted feeling as good as ever amid a gruelling pre-season.
Schmidt’s men are once again bidding to move beyond the quarter-finals for first time, but the Irish public have high confidence their side could even lift the Webb Ellis Cup.
But Best also predicted the most open World Cup yet, with Grand Slam champions Wales and a burgeoning England and South Africa also in contention.
Asked if the Irish public confidence adds pressure or belief, Best replied: “It’s probably a bit of extra belief. Our biggest pressure comes internally.
“New Zealand are the best team in the world and they are the favourites. But I also think this will be one of the most open World Cups.
“Anyone will feel they can beat anyone on their day. And it’s great that Ireland can be one of those teams.
“But we also know that, look at Wales and England in the Six Nations, we can lose to those teams too.”
Best believes Ireland’s maiden two victories over back-to-back world champions New Zealand, in Chicago in 2016 and Dublin in autumn 2018, have offered significant confidence boosts.
“That first victory against New Zealand, in Chicago, it felt like we pushed through a ceiling,” said Best, speaking as a FloGas ambassador.
“But it was hugely important to get the second one, to prove again that we can do it.
“We want to be a team that can prove we can beat anyone and we’ve not just shown it once, we’ve shown it twice now.”
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