Fraction of massive quiescent galaxy (selected at z = 2, 3, and 4; first, second, and third panel, respectively) progenitors that exceed S₈₇₀ flux densities of 1 mJy (dark blue), 3 mJy (purple), and 5 mJy (orange) vs redshift. At the redshift at which the distributions peak, a significant fraction of MQ progenitors exceed S₈₇₀ = 1 mJy. For example, 50%, 66%, and 67% of MQs selected at z = 2, 3, and 4, respectively, exceeded S₈₇₀ = 1 mJy at z ∼ 3.4, 4.3, and 5.5. These numbers are lower for higher S₈₇₀ thresholds: at their peaks, ∼3% of MQs selected at z = 2, ∼6% at z = 3, and ∼5% at z = 4 exceed 3 mJy.