Low Earth orbit satellites drag in the fringes of the upper atmosphere a lot more, so their lifetime in space, unboosted, is typically only a few years. If you

Low Earth orbit satellites drag in the fringes of the upper atmosphere a lot more, so their lifetime in space, unboosted, is typically only a few years. If your satellite dies, it's "self-cleaning." That said, an impact at this level can still spew debris into higher orbits, as the chaos of the collision can impart enough energy to some collision ejecta to change their orbit significantly. So you still don't want things bumping into each other.