I don't claim to know any specifics about how Karen and Ralph arrive at any particular decision. Generally, Ralph handles the hitting and Karen handles pitching and defense, if I remember correctly. Karen is also usually the disciplinarian. Karen calls all the game pitches. I assume Karen makes pitching changes, but that's a big assumption - I've never heard it said one way or the other.
Regarding the pitchers themselves, from what little I have seen of Bush, she cannot throw strikes. And since she's a control pitcher, not a power pitcher, an inability to throw strikes is fatal.
Moss is more of a power pitcher who needs to develop speed and pitch variance - which she is doing so. She has had some trouble throwing strikes, but not nearly to the extent of Bush, or say, Aucoin from last season. I am not surprised Bush isn't pitching. Moss I am surprised. I am not sure what is going on there.
Leach will be ok, she's a freshman, she just has to slow down. I worry about Geer at third. Almost anyone is an upgrade from poor McSwain, but Geer didn't perform exactly stellarly there in her earlier stint.
The team is doing "ok" but I expected more from this season and am frankly disappointed. The team lost Lewis and Tarango to graduation and Aldrete and Koenig to transfers. None of these were irreplaceable. With the pitching back plus the new pitchers and players I expected an improvement over last season's record.