What is the most overlooked consideration?

Quality stands for equipment and speakers.  What components and speakers are placed on dramatically influences everything from noise floor to sound stage and dynamics.  Few years ago I placed a very respectable system initially on an IKEA bench, (yes I know better), then finally placed everything on a proper Quadrasprie SVT stand, beyond shocking.  I knew better, but wow!  Everything radically fell into place.

Many items outside components and speakers are overlooked, I find that particular item the most frequently dismissed, misunderstood and oft poorly executed.

@mlapenta  Correct.  That Furutech combo is nuts.  I've not engaged in the dedicated 20A line, but do not doubt.  I've approached that part with a Puritan 156 conditioner, but you make a salient point attacking the source first.

Cumulative is the point here.  Improvement in all things has a cumulative affect in outcome.

OP:  What is the most overlooked consideration?  Don't believe quality components and room acoustics are the most overlooked.  Most here drilled down to exactly that, most overlooked.  Overlooked not the same as most important.

We've all been caught, confirmation bias leading us down a road only to discover "wrong thing".  Thought my DAC or preamp were experiencing a 60Hz ground loop.  It was the ceiling fan downstairs humming away.  Overlooked that effect.  Doh!