Just because you succeeded doesn't mean you didn't try.
Life is like a box of noodles
It may have gotten a nibble but empirically I still have a finger :)
Doesn't mean you were not bitten though.
If it wasn't accidental, that bite represents an attempt to bite.
It does mean they were not eaten.
A steel door is certainly harder than my skin and also certainly can't be used to "bite" me or puncture my skin (save for crushing it given enough force)
Just because it's harder doesn't mean it necessarily has the strength to tear off skin.