It is relatively easy to build a catalogue of possible reasons. There is, first, the difficult terrain that our road-builders found when they undertook the task of cutting roads through our hills and valleys and forests. I have often marvelled at the huge efforts made by our forefathers - in an era before earth-moving equipment - when picks and shovels were all that was available.
But the fact remains that our road network exhibits a higher proportion of tight bends, narrow stretches, cliffside edges and difficult surfaces than would be found elsewhere.
And, it has to be acknowledged, that while Kiwis all regard themselves as good drivers, we are on the whole I think regrettably aggressive, lacking in skill and discipline, and prone to taking risks.
In my view our drivers' skills, or lack of them, reflect several aspects of New Zealand culture. A largely rural economy has bred a commendable spirit of self-reliance but also an impatience with rules and restrictions. A large number of New Zealand drivers are family taught and have learned to drive on the farm and at a relatively early age, and have become used to light volumes of traffic on country roads.
Add to that a drinking culture and the fact that you need a vehicle to get anywhere and the ingredients are there for a high incidence of drink-driving which remains one of the banes of our lives - and our current struggle with the spread of meth and other drugs adds to the problem.
Read more: Rotorua road toll reaches five just two months into the year
Then there is the modern blight of the mobile phone. My wife and I have lost count of the number of drivers we have seen engrossed in a telephone conversation - or, much worse, texting - while driving; if you find yourself following a vehicle whose speed varies unpredictably or that wanders across the white line, you can be pretty sure that the driver's attention is elsewhere.
In any discussion of road accidents, the conversation will inevitably turn to foreign drivers, and it is certainly true that we have a higher proportion of drivers who are unfamiliar with our roads and traffic conditions than is the case in most countries - and, sadly, many reported accidents seem to involve foreign tourists.
Whenever this topic is raised, my mind goes back to when I was, as a young man, on a motoring holiday in Spain. I had become accustomed, as I thought, to driving on the right-hand side of the road, but it so happened that on one morning, my companion and I had crossed to the left-hand side to stop for a cup of coffee. When we resumed our journey, I pulled out, on to the nearer left side which naturally felt very familiar to me, and it was only when I saw the oncoming traffic approaching me on that side, that I realised my mistake.
So, we have to accept that accidents involving foreign drivers are all too likely and are part of the price we pay for our tourist earnings. The only remedy available to each of us is constant vigilance - vigilance we have to exercise anyway in respect of Kiwi drivers who may not know the road, or who are on the phone, or who are speeding, or who have been drinking or taking drugs.
Read more: Rotorua road toll reaches five just two months into the year
Improving our roads and increasing the policing are clearly part of the solution. But we also need to change our mindset.
Driving is not the carefree spin on the open road that we believe we are all equipped to undertake but is inherently dangerous. It requires all the skill, care, concentration and social responsibility we can muster.
