And predicting if this will happen is nigh on impossible.
That means that anyone who sets foot on Whakaari / White Island is playing a form of Russian roulette with nature. You step on the island in the knowledge you might be killed.
It is a waiver that is a significant level up from adventure tourism within human controlled boundaries.
Participants take a calculated risk when bungy jumping or even whitewater rafting.
The latter might involve nature but there is still an element of human control.
Not so with Whakaari / White Island.
This week's tragedy also raises valid questions about the tourism industry 85km inland from Whakatane, in Rotorua.
It is an industry built on geothermal attractions and, it seems, luck.
Rotorua locals live with the knowledge a steam vent or fissure may occasionally open up in their backyard. It doesn't happen often, but it can happen.
Is Rotorua a Whakaari / White Island waiting to happen?
There is a sombre irony in the delay this week for police and emergency services who will be involved in the recovery of eight people believed to still be on the island.
The inability to predict when Whakaari / White Island might suddenly blow led to a situation where the island was deemed safe.
That same inability to predict prevented people from going on to the island.
Putting aside the risk of hazardous gases, the eight people could potentially have been recovered in the days since the eruption.
It is an observation made with the benefit of hindsight.
But on Thursday, that became a moot point - the stalemate with Mother Nature ended.
Today, all things going well, police are heading to Whakaari / White Island to recover eight people.
The recovery operation will be a calculated risk.
The question remains - is the tourism industry prepared to continue to take a calculated risk and head back to Whakaari / White Island?