Comments by "Orwellian Horseman of the Apocalypse" (@DennisMoore664) on "They Are Watching Us: 5 Mysterious Objects in Earth's Orbit" video.

Part of the reason is that a comet or asteroid is not already in a stable orbit around the Earth, meaning it has a higher potential to be effected by Earth's gravity when it passes close by, while the orbiting debris is already balanced by the Earth's gravitational pull and maintains its stable path around the planet. There are other factors at play as well like the comparative mass of the objects, distances, etc. - celestial mechanics are complicated.
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@StuartAnderson-xl4bo Like I wrote, "there are other factors at play as well" of which spin and speed would be factors. And obviously any object at the closest point of its orbit around or passage past another object is going to be pulled closer to that object due to it's gravitational pull. And if the pull is strong enough the object will become captured by that objects gravity and either plunge into the object or become trapped in that objects gravitational orbit. But there are also objects which have a mostly stable orbit, other than having to account for atmospheric drag or the effects of other celestial bodies, and that's what I was referring to when I used the term "stable orbit".
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