Spectroscopic completeness fractions as a function of stellar mass (left) and density region (right) for J0152.7 (red) and J1252.9 (blue). The horizontal dotted line in the left panel represents 7 × 10¹⁰M_⊙, the dividing line between high-mass and low-mass samples. Completeness fractions for both clusters show a notable relationship to stellar mass but only a weak relationship to density. Uncertainties are determined using the bootstrap method resampled 10 000 times.