Properties of different galaxy samples at z = 1 in TNG100 (top row; comparable to the size of HLWAS-Deep) and TNG50 (bottom row; comparable to HLWAS-Ultra deep). The samples are as follows: gray = full sample of ﹩{\mathrm{log}}\,({M}_{* }/{M}_{\odot })\,\geqslant \,8﹩ galaxies; black = photometric sample with mock H-band magnitude m_H < 27.5 (top) and m_H < 28.1 (bottom); magenta, brown, and blue = samples satisfying both the photometric cut and a minimum SFR cut from spectroscopic emission line flux limits corresponding to 1×, 2.5×, and 5× the depth of HLWAS-Deep, respectively. Left: total number of galaxies in a given sample. Middle and right: completeness fraction as a function of mass and SFR. Very deep spectroscopy is needed to obtain fairly complete galaxy samples with which to trace the cosmic web.