boiling frog

Etymology
From a widespread misconception describing a frog slowly being boiled alive. The premise is that if a frog is placed in boiling water, it will jump out, but if it is placed in cold water that is slowly heated, it will not perceive the danger and will be cooked to death.

Noun

 * 1)  A person who, or thing which, is in a gradually worsening situation without any realization of the peril until it is too late.

Translations

 * Chinese:
 * Mandarin: 溫水煮青蛙, 溫水煮蛙
 * Serbo-Croatian: kuhanje žabe