The disconnect is that K-12 is not properly preparing students for college.  Most students are pushed through the system and GIVEN passing grades to move on to the next grade to not hurt their self esteem by being held back a year for not understanding the current material.  If you don't know basic math in 3rd or 4th grade and you move on, the problem compounds all the way through High School and you end up having to take remedial classes at college which may or may not solve the problem and the student drops out.