Not everyone is capable of learning or figuring it out.
Think about childhood dream jobs like rock star or astronaut.
Rock star: You need musical talent and stage presence, enough to entertain lots of people with your music. Me, I can sing in the shower and play some simple tunes on an instrument, but I’d starve if I tried to make it as a simple busker.
Astronaut: NASA requires a master’s degree in a STEM field, at least 1000 hours as a jet pilot, and that you pass a physical. Not everyone is capable of earning a master’s degree. Not everyone will be capable of learning to fly planes. And the physical – ever heard of a blind astronaut? Or how about conditions where your bones are brittle? Hop on the rocket - SNAP! Oops, broken legs. Etc.