rossdavidh parent
I feel obliged to point out that frogs, when put into a pan of water which is very slowly heated up, do in fact jump out when it gets too hot, contrary to the old story. But, perhaps humans are occasionally not as smart as frogs?
https://en.wikipedia.org/wiki/Boiling_frog
I haven't seen anybody sit in a hot tub until they died, usually we get too hot and then get out. That's nowhere near boiling. Obviously, the boiling frog trope isn't intended to be taken literally.