Why are you saying something like it is always true when it is only true given a certain clause is present? It says right in your link that that's only possible when your employment contract says it's possible. Seems dishonest of you.

I never saw anything like this when I worked at an early stage startup, and it's obviously something an employee who reads their employment agreement would ask to be taken out. I'd never work at a company with that clause.

>>> "Some startups"

This is necessary for stock options to work properly. The whole point is to make sure people want to stay and make a profitable company, not that they ditch the instant the stock passes some threshold.

On the other hand, this can lead to disaffected employees who are only staying with the job because they are waiting for their options to mature.

so, the way stock options work properly is that you can work to build a company, and if management blows the revenue, or fires you a month before exit, you get nothing of value out of it?