Because Kirk for a lack of a better word, pretty much sabotaged the show (http://www.cracked.com/article/135_6-beloved-tv-shows-that-traumatized-cast-members-life_p2/) to adhere towards his personal convictions/beliefs. I'm not necessarily talking about Julie McCullough, who Kirk got fired because she appeared in Playboy, but his immediate TV family? I'm also not necessarily talking about Tracey Gold's issues w/ an eating disorder (which allegedly, was in part due to the "fat jokes" that Kirk's character told to Tracey's character). I remember seeing an interview on I think Entertainment Tonight w/ Alan Thicke, who claims that he told Kirk that he had a contract that he had to honor. And if possible, he could help Kirk try to get a series on one of the Christian broadcast networks.