My son only applied to two colleges beside the in-state colleges, but he applied to 4 in-state colleges.
We did prepare for the worst. He plans to go to CC instead of going to a lower tier in-state college.
保底 is your bottomline. Ask yourself if you are 100% sure of the 底.
Examples:
Boy, USAMO, not admitted by Cal, nor UCLA
Girl, AIME, USAPHO, not admitted by Cal.