For my first 10 yrs out of school there was no job market for network operators specializing in BGP. Then I did that for a bit less than a decade. Then due to consolidation and mergers there's no work in that field anymore (other than the stereotypical "move to SV/NYC").
Another direction to go is my grandma did meaningless low skill BS work in an office shuffling papers as a clerk because she specialized in knitting and had amazing knitting skills, but didn't feel like being sentenced to life in a textile sweatshop in Vietnam, or where-ever clothes were being made at that time (Vietnam now, but in the 70s? Surely not the USA by then?). For my own example there's no way I'd tolerate 140 hour work weeks as a medical doctor although I'd probably have made a heck of a doctor, and I'm not living in poverty so forget academics/sciences, and I'm not living urban and working in an open plan office so forget SV. As a hobby I enjoy woodworking but as a profession the pay is bad and the working conditions are awful, also its not very deep so I'd get bored with it long before I retire, so ... no.
So you have chronological problems or retraining problems, and also people that are a skills match but hate the working environment. Maybe in a communist society the central committee could force my grandma to be a textile worker or force me to be a medical doctor or work at a startup, but there would be a lot of force involved.
Another direction to go is my grandma did meaningless low skill BS work in an office shuffling papers as a clerk because she specialized in knitting and had amazing knitting skills, but didn't feel like being sentenced to life in a textile sweatshop in Vietnam, or where-ever clothes were being made at that time (Vietnam now, but in the 70s? Surely not the USA by then?). For my own example there's no way I'd tolerate 140 hour work weeks as a medical doctor although I'd probably have made a heck of a doctor, and I'm not living in poverty so forget academics/sciences, and I'm not living urban and working in an open plan office so forget SV. As a hobby I enjoy woodworking but as a profession the pay is bad and the working conditions are awful, also its not very deep so I'd get bored with it long before I retire, so ... no.
So you have chronological problems or retraining problems, and also people that are a skills match but hate the working environment. Maybe in a communist society the central committee could force my grandma to be a textile worker or force me to be a medical doctor or work at a startup, but there would be a lot of force involved.