O levels were exams that were around when A level results had value, when all (most) degree courses were demanding, when people went to University for the education rather than the parties, when around 5% of school leavers went to University, and when most fresh grads had a choice of jobs because of the foregoing. I was tempted to add something about grants or the 11+ filter but thought I'd probably upset enough people already.
HFD
(tin hat firmly attached and egress plan intact)