This was a first for me, I have seen them loose and not properly torqued, but…:roll: 
Nice find. Oops
Looks like it had been under a lug to begin with. Would it be correct to say that the conductor on the left is over-stripped?
Not positive if it was over-stripped or not seated correctly… it appeared to be seated and over-stripped. but recommended that sparky check it since he will be there anyway. It was also moderately heated and discolored at the left lug.