How do you know when a stereo sounds good?

I listen and the music draws me in to stay. 

Question, where are these staunch objectivists defending their position that what subjectively sounds good is not necessarily the most important criteria where sound quality is concerned?

This, together with the previous (unquoted) sentence/s, is an oversimplification to the point of misrepresentation, and amounts to what is known as a straw man argument.

Folk who are not acquainted with this play on words are invited to google straw man. They are kinda "gotcha" arguments should you accept them as being an accurate representation.

I find that I have no need to listen when I know my system sounds good enough as it will always be there for me when I desire to listen to it. No more having to chase the dragon as I've already caught it. 

This question has been asked many times in similar ways on A'gon and I find it a bit amusing when some criticize the OP for asking it because of who he is when they afforded more latitude to others. Interesting. 

As for the whereabouts of the objectivists, who cares? 😀

All the best,
Nonoise

Being objective is a means to an end. It helps one make good decisions based on the information available. No good reason to vilify that. 

The objectivist has internal belief system that regulates audio equipment evaluations, It doesn't matter that nearly every audio system is bespoke, likely totally unique assemblage of  equipment, room, ears/brain etc. I accept I can't know the quality of sound others experience with all these variables in play. I accept at face value they hear what they hear. The internal skeptic in me remains, but I have capability of open mindedness, I can be convinced with new knowledge. Bottom line for me, why should I feel the need to impart my sound quality evaluations to another, I respect their evaluations as credible for them.

As other posters mentioned, a quality system for me is one that involves me emotionally. Sense/illlusion of performers in room has been my goal from the very beginning.