As many (most) have noted... how any component "measures" does not determine whether it sounds good to the listener, or not - that is just a FACT! More often than not, a component that sounds superb does not measure well... and one that does... not so much.
Though... some metrics are relevant (e.g. impedance, efficiency, noise, damping factor)... to, among other things, determine how well components "match" one another (i.e. system matching or synergy matters most). Tube components often measure poorly - though - they often sound the best, depending on the entire set up. And... excessive noise can obscure detail resolution, etc. While poor damping factor can ruin bass response and control.
So... consider selected metrics... when setting up your system... but... the sound that you finally achieve is all that matters. In fact... you will do better in assessing components from reviews, shows, manufacturers’ suggestions, and YouTube videos - determining the type of sound you prefer and can achieve.
In fact - the comments of Nelson Pass in this thread sum it up quite well: