For some, it’s not merely just a matter of “waiting a year.” The people I know who declined some acceptances for “another shot” didn’t have all their prerequisites completed and therefore financially benefit from staying another year at a CC (and paying CC rates or free with a BOG waiver) rather than going to a UC and paying additional costs for the same estimated bachelors graduation date.
Theoretically the only ones that really benefit from “trying again next year” are those that had a terrible start at CC (to help an upward trend) and those who didn’t meet all their prerequisites (a major criteria for admission). I think it’s fools gold (with a huge opportunity cost) to defer your UC admission if your not in one of those two cases.
Even “borderline” applicants don’t really improve their chances as the UCs historically increase their selectivity after each application cycle.