[1] The tint control is normally set by sight to create satisfactory skin tones in a picture.
Television sets produced in recent decades typically include a (sometimes non-defeatable) distortion of the color decoding spectrum, to minimize the visual effects of phase error and lessen the need to adjust the tint control.
Since the problem of phase errors in the real world became well known after the introduction of NTSC, the later PAL and SECAM color television standards attempted to correct for them.
(Severe phase errors result in picture grain and loss of color saturation in the PAL scheme.)
(This leaves the viewer unable to correct for color errors originating at the transmission site, however.)