Three reasons:
1) The atmosphere. Only the bigger rocks can punch through it to even create a crater
EDIT:1.5) Oceans. They’re 70% of the earth’s surface. If a meteorite manages to make a crater on the ocean’s floor, it goddamn earned it.
2) Erosion. Surface features on earth get worn away. Mountains get turned to sand, depressions filled sediment. A lot of craters are actually still there (like the famous dinosaur killer Chicxulub crater), but invisible to the naked eye. I guess this is also 2.5) vegetation and water.
3) Plate tectonics. A lot of craters don’t exist anymore, because the crust they were punched into doesn’t exist anymore.
The moon lacks all of those. Any feature on it’s surface will stay there.
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