It is a truth few politicians want to acknowledge. From the moment they are elected, they are on borrowed time. In the past 19 years New Zealand has had four Prime Ministers.
Each has temporarily had the keys to the ninth floor of the Beehive on loan from the public of New Zealand. Politicians come and go, but over that same 19 years one woman has had uninterrupted access to the Prime Minister's office.
She is not a household name, but most nights Jaine Ikurere turns up to work at Parliament to clean up after the politicians.
It's not a job many people would want, and particularly not for $14.60 an hour.
And Jaine is not even at the bottom of the pay scale for cleaners at Parliament. She's a supervisor. Most of her colleagues get just $13.85 an hour, a paltry 35 cents an hour over the minimum wage. For a forty hour week that works out at just $554 - and that is before the Inland Revenue Department takes its slice.
Cleaners at Parliament are currently asking for a pay rise to $15 an hour, but so far without luck. They do an honest day's work, they deserve a decent living wage.
And they are not alone. Currently more than 200,000 people are paid the minimum wage. Many of them will receive top-ups from the state, in the form of Working For Families or the Accommodation Supplement. They need that taxpayer support because they can't live on their weekly pay packet.
Lifting the minimum wage to $15 an hour, as proposed in my Bill awaiting debate in Parliament, will not change that overnight, but it is a step in the right direction.
The truth is New Zealand is a low wage economy. Despite National's promise of a brighter future and closing the wage gap with Australia, every week a thousand kiwis leave New Zealand for Australia.
Not only is the unemployment rate much lower across the Tasman, and the average wage much higher, the minimum hourly wage is almost $NZ20.
Of course, increasing the minimum wage will come at a cost to business. All up, it's likely to add about $427-million dollars to the country's annual wage bill. But that money will not disappear from the economy, it will quickly be spent on essentials, from food, to clothing to school fees.
Inevitably, some business will say they can't afford to pay more in wages. There will be dire warnings of job losses and a lack of opportunity for young people looking to break into the job market. And if we were talking about a radical increase - to say $30 an hour - that would undoubtedly be true.
But a $1.50 an hour increase is not going to force hundreds of employers around the country to suddenly go bust and sack their workers. In fact, no direct link between lifting the minimum wage and job losses has ever been proved.
What has been proved is the destructive effect of poverty and inequality. The incidence of poverty-related illness in New Zealand is a national disgrace, and costs taxpayers hundreds of millions of dollars a year. Giving low-income workers a boost in wages will help thousands of families pay their power bills and help them afford doctors' visits and prescriptions.
This is an issue of fairness and basic human dignity. Every night the cleaners at Parliament turn up to work when most of us are at home with our families. They work hard, and they deserve a decent pay cheque at the end of the week. That's something I hope MPs from across Parliament will reflect on when they turn up to their freshly cleaned offices - and when they come to decide whether or not to increase the minimum wage.
* Dr David Clark, MP for Dunedin North, is Labour's revenue spokesperson.