Define objective criteria for the quality of a piece of music

Everyone has an opinion on this topic, even those who "like all kinds". Highly differentiated opinions tend to be held quite strongly, as in a lover of ‘classical’ music who categorically dismisses all music published after 1918 – or adhering to a single genre such as heavy metal. But seriously, what bugs me more is when people refuse to discuss their criteria of quality and instead give in to some kind of lukewarm relativism. So, this is your chance to have it out. How about complexity (rhythmic, harmonic, structural, etc.)? Technical virtuosity? Emotional impact? Popularity (just kidding)? Whatever makes you like a piece, spelled out and described as concisely as possible in objective terms. I suggest we focus on criteria and attributes, rather than merely placing your favourite example front and centre.