From Wikipedia:
Keith Moon and John Entwistle, drummer and bassist for The Who, respectively, suggested that a possible supergroup containing themselves, Jimmy Page, and Jeff Beck would go down like a lead zeppelin, a term Entwistle used to describe a bad gig.[30] The group deliberately dropped the 'a' in Lead at the suggestion of their manager, Peter Grant, to prevent "thick Americans"[19] from pronouncing it "leed".[31]
Keith Moon and John Entwistle, drummer and bassist for The Who, respectively, suggested that a possible supergroup containing themselves, Jimmy Page, and Jeff Beck would go down like a lead zeppelin, a term Entwistle used to describe a bad gig.[30] The group deliberately dropped the 'a' in Lead at the suggestion of their manager, Peter Grant, to prevent "thick Americans"[19] from pronouncing it "leed".[31]