UPMs should be filed if Profile Managers do not respond accordingly. With research, these profiles can be fleshed out. Looking at the PM's watchlist to see if it is a duplicate or others with the same surname may give indication of the era or region the orphan is from. Another approach is to search for similar name on Geni, Ancestry, and FamilySearch trees to see if the person uploaded a gedcom there and it remained intact.
If, after looking at all those places, still nothing turns up, the profile can be placed in the Unknowns category, but do not change any names or details on the profile. It should be used for the same name it originally was so keep the changes log consistent. Leave notes on the profile where research happened so others do not double up on your work.
Deletion should not be used. If there is some extenuating circumstance that indicates it, please get in touch with a Team member.