Why do NOS Tubes sound better than new tubes?

Is manufacturing really that backwards in todays techno world? What is the real reason that todays tubes cannot equal the tubes of yesteryear?

tubed108-26-2011 2:39pm

hifihvn Details Discussions Posts This discussion Message User 943 posts 08-26-2011 at 07:32pm Copy Comment URL Report Comment Edit Delete This was posted recently. You could see in the old videos how much they tried for quality. [http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1314237934&openusid&zzHifihvn&4&&]
hifihvn Details Discussions Posts This discussion Message User 943 posts 08-27-2011 at 12:51am Copy Comment URL Report Comment Edit Delete They kept the machine for several decades so tube quality at the end of the machines life was relatively poor. Could explain why there are so many complaints about new records people have to keep returning.
hifihvn Details Discussions Posts This discussion Message User 943 posts 08-28-2011 at 10:51pm Copy Comment URL Report Comment Edit Delete Also Western Electric and RCA in the film industry sought after better sound. Most likely another big profit area.