But the insurance money and government support that pours into an economy after a disaster, and the extra activity that repairs and reconstruction generate, do have a stimulatory effect.
So, weirdly, economies can experience a bump in GDP growth in the wake of disaster. That happened after the Christchurch earthquakes and provided some useful momentum with the country still in recovery mode post-Global Financial Crisis.
Unfortunately, the timing of the flooding in the past week is entirely unhelpful given where we are in the economic cycle. The last thing we need is more stimulus.
The Reserve Bank is already hiking interest rates to slow economic activity and, hopefully, get inflation back under control.
Economists say it is still too early to be sure of the overall economic impact of the flooding. But, on balance, they see it as being inflationary
The economy is running at capacity and the construction industry and food producers are struggling to keep up with demand, prices keep rising.
The damage to crops in the fertile belt around Pukekohe will mean shortages of fresh vegetables and more upward pressure on food prices.
Roading damage will also add extra logistical pressures for food companies and supermarkets, which will inevitably be passed through to consumers.
The timing for construction costs is also terrible. The first signs of inflation easing in the building sector were just starting to show in the latest Consumers Price Index data.
The sudden increase in demand for construction products and workers is likely to blow that out of the water for the next few months.
If there is any consolation it is that economists expect the Reserve Bank to look through the short-term price shock the flooding will cause and will remain focused on core inflation over the next year to 18 months. There are signs that it has peaked.
In the US and Europe, they are already celebrating (perhaps too early) with stock markets booming back to life. In New Zealand, the evidence has been more subtle - buried in recent CPI and labour market data.
The impact of flooding may make the evidence even harder to discern in the next round of data.