[notacoward]

How much is that "market for people who understand your software" worth? Sometimes those people are your competitors, using your own code plus local improvements (or "improvements") to sell against you. It's not as simple as saying you'll always win or you'll always lose. There are both opportunities and risks, which have to be weighed on a case by case basis. I've seen my own code sold against me too many times to believe permissive licensing is always the right answer.