There is a theory that this was not from wind, sand, rain, stone scavenging. Khafre pyramid at Giza was under sea for a very long time.

Karst undercutting erosion of the Tura limestone cap of the Khafre pyramid at Giza. The erosion turns up parabolically at both ends, characteristic of wave-action induced seawall erosion at 90 degree corners in harbors and ocean breaks.

The Khafre Pyramid shows signs of erosion that seem to have been caused by seawater.