A conservation biologist is estimating the population density of the rare alpine herb Saxifraga oppositifolia on a mountain scree slope. The biologist uses a portable GPS receiver to navigate to twenty randomly pre-generated geographic coordinates to place their 0.5 m×0.5 m0.5\text{ m} \times 0.5\text{ m}0.5 m×0.5 m quadrats.
State the primary scientific reason for generating these coordinates randomly rather than selecting sampling locations by visual inspection of the slope.
