I don't see how this answer was worthy of a flag. I think distorted's trying to say that the DS was modified by its previous owner. I could see this answer being downvoted, but I don't think it should've been flagged.
And also, to reply to XYchampionWTF, I don't believe it matters if it is a DSi or 2DS. Both have the possibility of being harmed by their previous owner's modifications. This isn't my answer though so don't take my word for it.