A lot of high school athletes and parents have the misunderstanding that a college coach can pull a scholarship once at school for "poor play." That's not really the case. While scholarships are renewed on an annual basis each summer, and a coach can ask a scholarship athlete to leave the team there are protections in place for student-athletes. When not performing up to expectations it is the coach's responsibility to work with the athlete but the scholarship can't be yanked for poor play.
Here are the main valid reason for pulling an athletic scholarship:
* Failure to maintain the required GPA or full-time academic class schedule (12-15 units typically)
* Breaking team or athletic department rules
* Disruptive attitude (this one is subjective and can be grounds for argument)
* Failed drug test
* Violating team/department/school/NCAA policies