Quoted from vid1900:Back before samplers and electronic gadgets were good enough to use live, Ozzy would have other singers backstage who would sing his songs for him.
You can't be nominated for "best metal singer of all time" if you can't sing live.
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That was back when he was to wasted to sing. I have seen him live a couple times and as recently as a few years ago and sober Ozzy destroyed it. Sounded fantastic sober and put on a heck of a show.
Ozzy lemmy or axl get my votes