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The Interpreting Indicators of Rangeland Health (IIRH) is a qualitative assessment used to evaluate ecosystem health on rangelands worldwide. The assessment provides an evaluation of three attributes of rangeland health: soil/site stability, hydrologic function, and biotic integrity to identify sites that are at a risk of degradation or have resource problems. To evaluate each ecosystem attribute, 17 indicators of range health (e.g., presence and amount of rills, vegetation composition, soil aggregate stability) are rated with respect to departure from reference condition for the study ecological site. The indicator ratings for each ecosystem attribute are then examined and an overall attribute departure from normal rating is determined. A “preponderance of evidence” is used to evaluate if an attribute is departed from reference condition. However, in practice, certain indicators may consistently receive more weight in rating attributes due to a) observer bias towards the impact of a particular indicator or b) low observer confidence in rating an indicator. We examine 1,244 IIRH assessments conducted between 2011 and 2013 throughout the Great Basin and show that some indicators (e.g., invasive plant species) have greater effect on attribute ratings than others (e.g., soil surface loss and degradation). These biases can skew the overall site evaluation and can have implications for land managers utilizing these assessments.