Photo-z performance as a function of the ground-truth redshift precision used for training the networks. The training redshifts are the spectroscopic redshifts, the PAUS+COSMOS photo-zs, COSMOS30, and a set of CFHT photo-zs in COSMOS. Red points correspond to training on the spectroscopic sample (around 6000 galaxies). The green and red points show the training sample extended to COSMOS galaxies with photo-zs (around 15 000 galaxies). The blue lines show the expected photo-z performance as a function of target redshift precision. The true redshifts, the spectroscopic redshift in the COSMOS2015 catalogue (solid blue line), and the simulated redshift in the PAUS mock (blue dashed line) are scattered with precision in 0.001 bins. The top inset zooms into the framed area in the main plot (lower-left corner)