Orbital decay comes from something. At some distance from Earth, you run out of somethings (most critically: atmosphere) decaying an orbit. So past a certain d

Orbital decay comes from something. At some distance from Earth, you run out of somethings (most critically: atmosphere) decaying an orbit. So past a certain distance, orbits are effectively "forever" ones. It just takes more energy to get there, which is why the ISS is where it is.