Success rate (𝒮ℛ) vs contamination rate (𝒞) for the mock EWS-SF_sim, colour-coded by the applied redshift probability threshold (z_prob). The top panel shows results for a flux threshold of 2 × 10⁻¹⁷erg s⁻¹ cm⁻², while the bottom panel corresponds to a higher threshold of 2 × 10⁻¹⁶erg s⁻¹ cm⁻². Different symbols represent galaxies in distinct stellar mass bins. As a reference, the black curves connect the points corresponding to the mass bin log₁₀(M_*/M_⊙)∈[10, 10.5].