One reason:
LAWSUITS. Networks do not want to get sued because you thought they stole your idea. When creators pitch an undeveloped idea anybody could have come up with ... they think a show that has anything do with their idea was stolen from them. For instance, Marc Zicree was a writer on “Star Trek Next Generation” and he told us there were one, or more, lawsuits filed for every episode by people who claimed their ideas had been ripped off. Are ideas ever stolen? Yes. Does it happen as often as rumored? Absolutely not.Also see: Help, Hollywood Stole My Idea (or Script)!
