Speaker cable arrows???

Trust your own ears. I believe that directionally and "golden ears" are all BS but I usually comply anyway "just in case" ;-) 

Its like the Twilight Zone episode where the guy goes for gas and cuts through the forest and winds up in this town where everything looks the same except nobody knows anything that's happened the last 30 years. 

Here ya go!
https://www.psaudio.com/askpaul/why-do-cables-have-direction/

I know this for sure, if the cable comes with a project box and or a lump or a bump in the run, direction does matter.. Will it harm anything? NO. Will it change the way it works? YES, Will it change the sound, YES.

If the cable has a high pass filter, hooking it up backwards, reversing polarity, would turn the High pass filter into a low pass filter.  Think about that one. A  resistor and cap from pos to neg = a 6 db HP first order filter.
If you reverse it,  it becomes a cap and resistor, network. 6 db LOW PASS first order filter. 

That network would burn out in  about 30 seconds @ 20 watts....(depending on the component ratings)

Second the inductor in a network cable on the pos leg would then be on the neg leg, what would that do?.... I duno..
 
If it's not a network cable, one way, MAY or MAY not  sound better after it settles in.  The cable is all ready broke in (so to speak) so it need to settle in a bit and flow in "a" direction.. The cable will sound better in hours or days as opposed to weeks or months. 

Direction matters

Be aware static discharge to the cable ends can screw thing up to.. cover the ends of unused cables. Ground yourself OUT.... Then do your work..
A simple 5 second process that VERY few observe... Why do it? It adds to the longevity and quality of the cable being installed. Handle your cables with care.......Hook the speaker end first, (why? no place for the discharge to go, if the other end is still covered) then Discharge yourself on the preamp, phono ground, unwrap the cable end and plug in.

Ok 22 cent worth....or 2.22...

Regards

Doesn't matter.