I see it as a game where investors get a better deal than the founders wanted. There is a lot of innuendo on the "we're not really interested, unless there's more upside for us" and the founders are then under pressure to up forecasts.

I think the investors believe the business is sound. It's just a way to get it for a better price.

Of course, if the business is a unicorn, none of this applies.

You're never going to make money from that. By the time you're presented with the opportunity to use them, you're on the losing end.