How u cannot see such an obvious point.

Let's say your private school has 10 best students (name A,B,C,...), and another 10 less competitive students (name a, b,c,d,...).  They all apply to the 8 ivies. Yale is interested in accepting one from the school and admitted A. Probably the other 7 colleges find A is the best and admit him too. Finally, the school has 8 acceptance, all of them go to student A, leaving the other 19 rejections. The counselor would get fired immediately for such a bad performance with one 1 get into ivy. However, if the counselor arranges the application process, paring A to Yale, B to Harvard, C to Brown, ... This way can ensure that the best results would be achieved. Fewer applications but better acceptances.