The world in which Lithops olivacea is established looks rough and rugged.
This dry and often hot environment can, however, be cool to lithops. Heat is reflected away from the ground by the white quartzite. Big rock shade reduces the direct sunshine hours received by many plants living here by much.
Moisture retention here may also by preferable to what it would be on a bare, stoneless flat patch, subject to the same climatic conditions a short distance away.