[Question] How often do series C startups fail to exit?

How often do series C startups really fail? By fail I mean never have an acquisition or IPO. Internet says 80% (see https://​​medium.com/​​journal-of-empirical-entrepreneurship/​​dissecting-startup-failure-by-stage-34bb70354a36) but this seems very high to me.

Most Series C companies are worth in the 100-200M range, the one I’m at is worth 270M. How does all the value just evaporate? What happens to the companies that “fail”?

Asking to decide whether to exercise my options. I only need my company to exit at 41M to break even. I am bearish on the company but with around 40M in ARR it is hard to imagine it not exiting.