It's not clear when METALLICA will call it quits.  They might still be rocking into their 90's.  But according to JAMES HETFIELD . . . once it's over, it'll REALLY be over.

In a new interview, he specifically called out KISS and THE SCORPIONS for doing massive promotions for their "farewell tours" . . . and then deciding NOT to retire.Quote, "I don’t think that’s fair to anyone.  Kiss [did a] farewell tour for the 10th time?  [The] Scorpions were done, and then they [toured]?  You can’t say that and then not DO it.

Meanwhile, drummer LARS ULRICH says he almost quit the band back in 2001.  But now he hopes they NEVER stop rocking.  Quote, "I don't think I want to do music once Metallica ends.  Hopefully, it will last FOREVER."

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