The first thing to understand about college and university admissions is that it is not all about you. A school has a certain number of places available and a certain applicant pool and the job of the admissions staff is to match the applicant pool with places available. In a year with more qualified applicants than there are places, that means that the admissions staff must select the best of the applicants that meet the minimum qualifications; in years with a weaker pool, less qualified applicants may be admitted.
Also, many factors other than simple GPA and ACT/SAT scores may affect admissions. For example, if two students have the same scores, but one is an extremely talented musician or outstanding at sports or has been really active in community service, and the other applicant has just met the minimal numeric qualifications without the strong extracurriculars, that second candidate will be less likely to be admitted.