Why might you expect an older surface of a moon or planet to have more craters?

An older surface of a moon or planet is expected to have more craters because it has been exposed to space for a longer period, allowing for more collisions with asteroids, comets, and other debris. Over time, these impacts accumulate, creating a higher density of craters. In contrast, younger surfaces may have been geologically active or resurfaced, erasing or covering existing craters. Thus, the number of craters serves as an indicator of a surface's age and geological history.