Please enlighten us

Founder stock almost always convert to common not preferred. Carta article about it: https://carta.com/learn/startups/equity-management/founder-s...

I recommend researching a topic at least a little bit before going on and commenting on it

This serves my point not yours, the process is often very misunderstood by those being promised the equity, and it's often "converted" in ways that dilutes or outright takes away most of the value by the time the employees ever see financial gains from the equity.

That’s not what happens. Literally TFA covers the term “founders stock”. It really is a meaningless term to refer to common stock held by a founder.