Trouble is, I know a lot of people who used this extreme approximation to their detriment. In general, there's a huge difference between "worthless" and "cheap

Trouble is, I know a lot of people who used this extreme approximation to their detriment. In general, there's a huge difference between "worthless" and "cheap". If it's cheap, you might want to get more of it - and then it's valuable. If it's truly worthless, getting more does not help. That's how multiplication works with small numbers and with zero. Zero is a special small number. So I claim that "equity is cheaper than they make it sound" is absolutely the right thing to say to yourself (not to the employer), while "equity is worthless" is a terrible thing to say to yourself if you then stay at the place. (It's potentially a sensible thing to say to yourself if you intend to leave, and especially if you're leaving for something that looks both good and not that risky.)