He declined to apologise for the comments and defended them by saying that he thought it was off the record – which is incredibly naïve for a man who was wearing a lapel microphone and is campaigning on the premise of being an experienced operator.
He should have perhaps just said it was locker-room talk, a bit of banter between the boys, a case of blowing off some steam before doing the hard work of representing New Zealand's biggest city with poise and decorum.
Comments inadvertently uttered into a hot microphone should never be brushed off. They offer a rare glimpse at the man behind the PR image. They lift the veil on what a politician is really like when he thinks no one is watching.
Trump's "grab them by the p****" comments are perhaps the most infamous case, but there are myriad other examples of politicians uttering remarks that would come back to bite them.
Mitt Romney's presidential campaign was derailed when he told a group of donors: "There are 47 per cent of the people who will vote for the president [Obama] no matter what" because they are "dependent upon government ... believe that they are victims ... believe the government has a responsibility to care for them ... these are people who pay no income tax."
In speaking about those comments later, Romney admitted that it really hurt his chances of becoming US President. It hurt so much because it played directly into the perception many people already had of him: basically, that he was an out-of-touch rich guy, who didn't care about the poor.
Former UK Prime Minister Gordon Brown also landed in hot water in 2010 when he described a critic who had queried immigration levels as a "bigoted woman". Brown would later be forced to visit the woman and apologise in person before also apologising on live television.
These moments offer the harsh unscripted reality of what these people actually felt comfortable saying behind the scenes. They also served to confirm what some members of the public already thought about these people.
So what can we deduce from Brown's comments made behind the scenes?
To start, his sense of humour is juvenile at best and crass at worst.
As former Herald editor Tim Murphy pointed out, the gag isn't even original. In the 2000s, Auckland mayoral dropout Leo Molloy put rubber mats bearing Herald branding in the urinals at his restaurant Euro.
If you're going to engage in some impromptu stand-up comedy, at least try to come up with something that hasn't been done before.
One lame thing about Wayne Brown’s comment about putting @simonbwilson photos on council urinals is that it’s unoriginal. Leo Molloy, as Euro owner, put rubber mats made with the Herald gothic masthead in his urinals in the 2000s, when I was editor, over some imagined slight.
Brown slipped into his comedy attempt in response to the fact that Herald journalist Simon Wilson had dared to tell readers the age of a mayoral hopeful. (Something that had, in fact, been reported earlier by other journalists).
Let that sink in for a moment.
Brown, 76, was so offended that he created a fantasy in which he would humiliate the journalist every single day after becoming mayor.
Pressed on the matter during Newshub Nation, Brown stressed that Wilson had been picking on him from the beginning of his campaign.
Let it be clear, Brown isn't accusing the mainstream media of a widespread campaign against him here. If anything, the media, including the Herald, has been relatively kind to him. He seems to be triggered simply by the fact that a solitary journalist would dare to question his ability to be mayor of Auckland.
It's important to remember that the mayor only has a single vote on a council of 20. He needs the support of other people in that group if he is to get anything done. Good mayors are good collaborators.
In a recent interview with the Herald, outgoing mayor Phil Goff said one of the toughest lessons he had in his transition from central to local Government was learning to work with people who don't necessarily share his view of the world. Goff said some of the best councillors he had were affiliated with the National Party and would have been political enemies if he had encountered them in central Government.
A mayor doesn't have a caucus to lean on for support and cannot simply act with impunity when others disagree with him.
Being an effective mayor of the Super City means putting your ego aside and listening to the views of those around you to reach a consensus that drives the city forward. It means you need to get used to the idea of being challenged – often.
Perhaps Brown is so self-assured he doesn't believe any right-minded person would ever dare to question his brilliant ideas.
He wouldn't be alone among politicians and business executives to have fallen into this trap.
In his excellent book, "Why do so many incompetent men become leaders?", Tomas Chamorro-Premuzic argues that we often mistake confidence for competence.
"We assume that confident people have more potential for leadership, but in any area of talent, including leadership, there is just very little overlap between confidence – how good people think they are at something – and competence – how good they actually are at something," says the writer.
Brown may be supremely confident in his ability to make the changes he thinks Auckland needs. But peeing on those who disagree with him probably isn't going to get him any closer to his objectives.
• Damien Venuto is the host of the Herald's daily The Front Page podcast and a media writer.