Shuttle was supposed to be two different vehicles: a potentially reusable but a cheap unmanned heavy lift vehicle plus a small reusable manned shuttle.
A lot of the vision was actually around building orbital solar arrays (remember the microwave power plant from sim city 2000?) to resolve the oil crisis.
The oil crisis went away and the microwave arrays idea didn't make much progress and shuttle' budget got cut until they could only do one vehicle, so they tried to combine both and have a reusable heavy lift manned space glider.
But because the microwave arrays weren't going to happen nor was the earlier L1 space station idea (and skylab deorbited before shuttle's first launch) they had nowhere to shuttle anything to, so instead they just ended up with a heavy lift LEO launcher that had people onboard for some reason.
Ofc they eventually got the ISS as a destination, much later.
A lot of the vision was actually around building orbital solar arrays (remember the microwave power plant from sim city 2000?) to resolve the oil crisis.
The oil crisis went away and the microwave arrays idea didn't make much progress and shuttle' budget got cut until they could only do one vehicle, so they tried to combine both and have a reusable heavy lift manned space glider.
But because the microwave arrays weren't going to happen nor was the earlier L1 space station idea (and skylab deorbited before shuttle's first launch) they had nowhere to shuttle anything to, so instead they just ended up with a heavy lift LEO launcher that had people onboard for some reason.
Ofc they eventually got the ISS as a destination, much later.