Without a doubt, the most widely used cliché in the halls of power is that "the leader of the Opposition is the hardest job in politics".
It's a phrase that's been repeated by the likes of John Key and Jacinda Ardern – who both went on to become Prime Ministers after a stint in Opposition (a particularly short one for Ardern).
Others have not been so lucky but still agree that the job is tough.
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New National Party leader Todd Muller is experiencing that first hand at the moment.
After a good first speech, Muller's momentum began to fade – in fact, he's had a doozy of a few days.
He has had to address the outrage over his Make America Great Again cap, the "whiteness" of his front bench and the leaking of confidential caucus information.
And he hasn't even been in the job a week.
Fortunately for Muller, he's not the first person to experience the frustrations that come with being the leader of the Opposition.
"I worked like a dog," former National leader Don Brash told the Herald, of his time in the job.
"You are, by definition, always on the back foot."
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Brash said that Muller should have killed the MAGA cap story from the beginning, rather than respond in a way that dragged out the story for days, culminating in a backtrack .
"The story gathered a momentum of its own, which was pretty ridiculous," Brash said.
"He should either have kept it well out of view or laughed it off and said 'I gathered some memorabilia when I was in the US in 2016 ... but I'm not in any way a supporter of the kinds of policies the President is advocating.'"
Brash is well known for claims in his Orewa speech in 2004 about special treatment for Māori, and he said Muller endorsing Paul Goldsmith as a Māori MP on National's front bench was not the best move.
Facing questions about an all-white top 12, Brash said Muller had nothing to justify.
"My reaction to that is, 'So what?' There are no Asians on the front bench either. He shouldn't be the least bit defensive about that.
"He should not be choosing his people on the basis of ethnicity."
As far as Opposition leaders go, Brash is considered to be one of the most successful of recent times.
He brought National from its worst-ever election result in 2002 – when it collected just 21 per cent of the total vote – to polling as high as 48 per cent in 2004.
Despite this, he failed to lead National to an election victory in 2005.
He agreed that leader of the Opposition is, indeed, the hardest job in politics.
"Why? Because you're expected to have an informed opinion on everything the Prime Minister has an opinion on and you only have a tiny fraction of her resources," he said.
"The Opposition leader has to be seen as someone who's offering constructive suggestions, not just criticising the Government."
This can be tough when a major part of the job – as the name suggests – is to oppose what the Government is doing.
Brash's comments are echoed by former Labour leader David Cunliffe, who took over as the party leader in August 2013.
"I think it's an extremely difficult job," he said.
"Having done a range of jobs both inside and outside politics it's certainly the most challenging job I've ever had the privilege to do."
In some ways, Cunliffe's time in the job is similar to the position Muller finds himself in at the moment.
The Government is experiencing a "Covid bump" in the polls – it's receiving more support at a time of a tragedy.
The latest One News/ Colmar Brunton poll – taken before Muller took over as leader – showed Labour was at 59 per cent.
Cunliffe said when he was leader, Prime Minister John Key "was riding high coming out of the Global Financial Crisis rebound."
He said there is a natural tendency of voters to rally around the flag during times of crisis.
"And if you're leader of the Opposition at a time like that – you really have a headwind which there is nothing you can do about."
He also said Opposition leaders don't have a lot of resources to "take on the might of the Government of the day with their armies of highly-trained civil servants".
"You're kind of fighting with one hand behind your back."
Asked for his advice for the leader of the Opposition, he said: "Have a clear game plan over time".
Although no plan is perfect, he said it's important an Opposition "plays its own game, rather than always being in responsive mode."
He's a senior minister now but Andrew Little had his fair share of struggles when he was Labour's leader in the mid-2010s.
"The reality is you're not a decision-maker – you seek to influence. But the reality is most people want to know about the decisions the Government of the day is making and how that affects them," he said.
"The Opposition has got to continue to have a voice and present an alternative and maintain some discipline when, sometimes, getting traction is not the easiest thing."
Little said the job can be frustrating at times, but it's important to think carefully about what issues you pick up.
Asked for his advice for Muller, Little said: "I don't have any advice for the leader of the Opposition – I'm in the Government".