This method is influenced by assumption that at time zero of a planet, the surface had no craters and the craters which followed time zero are spatially and temporally random. It can only be applied with accuracy to planets which have little to no tectonic activity, since constant resurfacing (like on Earth) would distort the true number of craters over time.
This method is based on the idea that at the start of a planet's timeline, its surface lacked craters and subsequent craters appeared randomly in both space and time. It can be applied precisely only to planets with little tectonic activity, as continuous resurfacing (such as on Earth) would obscure accurate crater counts over time.