Ice expands up and not out for the most part and you have alot of surface area to go up.
Sooooooooooo many owners cover the pool and forget about it for 5 months. They all look similar.
Once it freezes you are stuck with whatever happens after. I always kept an eye on the extended forecast and tried to drain right before any big freezes so I had even less to worry about when whatever happened happened. But it was mostly for my own piece of mind. Cheaper than going to the Dr for pills to sleep better, I always say.