What's an extreme circumstance? Some people are very hard on themselves and have a higher tolerance for what amounts to mistreatment. To them, extreme circumstances would amount to actual physical abuse or constant, in-your-face shouting, for example.
To someone else, extreme could mean that they sense a strange bitterness rather than team harmony, and they can't focus at all as a result. They can't focus, so they can't work, and they are committed to doing their best or nothing at all, so they leave.
Others get a strong intuition. For example an employee had a really bad feeling about his workplace. It wouldn't stop--something was off. He contacted someone who used to work there. She said she had sued, and won a judgment against the company for an invasion of privacy and discrimination by the CEO.
This person hasn't themselves suffered through that other person's experience; they simply had a bad feeling and learned something really awful about the company. Is that extreme circumstances for them?
IMO there is work to be done around that phrase "extreme circumstances."