A long harsh digital trip - final meter?

So the digital signal manages to find its way to a utility pole in front of your house. Then enjoys a coaxial sprint to a modem, and then head over to a modem, router and then into a Roon nucleus. Up to this point, a rugged unprotected harsh trip. And now this signal flows along a very refined ubs cable and arrives at a dac for final prep work before reaching a high end system. 
      So why does the final leg of the signal’s journey inside a usb cable seem to matter so much toward improving sound quality? What happens here to revive a digital signal that has traveled hundreds of disgusting dirty miles to reach the analogue chamber of rebirth? So I guess it’s possible to truly transform and correct a digital signal during a very short journey thru a usb cable?