Rest-frame UVJ diagram of the selected sample. The stars are all the galaxies observed in the COSMOS Wall volume by the LEGA-C survey, while the red points mark the spectroscopically selected quiescent galaxies. The solid black line is the separation between star-forming and quiescent galaxies as defined in Eq. (4) of Williams et al. (2009). The dotted line divides younger quiescent galaxies (on the left) and older quiescent galaxies (on the right) according to Whitaker et al. (2013).