Here is what I suspect happened with Pacini. This is how they treat a lot of the girls the are ready to "move on" from. (this is just a generalization, and her situation very well could have been different).
Each fall and spring, the coaches and players have an exit interview to see how things went and how they can improve. In the fall, most things are along the lines of: "you are starter material, just work on hitting your cut off and tweak your mentality at the plate". In the spring, for those the coaches are ready to "move on" from goes something like this: "you didn't live up to our expectations this year, I'm not sure you are ready for softball at this level, in fact I'm thinking of only using you as a pinch hitter, and probably only let you run next year, if I even bring you back at all". The coaches are trying to make the players leave to free up the money. Freudian hydraulics (psychological pressure).
Well the kid has to decide if they want to play for such a coach, or move on to another school, or in Pacini case, go to school and get your degree on your scholorship.