Habitable ringed planets are a science fiction trope that some people laugh off as impossible.
Except, apparently not.
The math indicates that Mars' moon Phobos is doomed. In 20 to 40 million years it's going to get too close to Mars and break up...
...and turn into a spectacular ring that will last for up to 100 million years.
However, it would be bad news if this happened on an inhabited planet, as some of the debris would no doubt hit the surface in a meteor storm you wouldn't want to be under.
On the other hand, Earth life recovered from the impact that killed the dinosaurs in far less than 100 million years. So, maybe?