I think you'll find this is not a typical case of returning an item under the "change of mind" policy. What you've suggested is return the item, incomplete when it was originally complete, or state the item was faulty when it never was. Now I'm no saint myself but if I make a mistake then I'll take it with a grain of salt and move on rather than try and justify it by returning it under the pretense of "faulty" or "incomplete". Turtleboy has already stated that he's made a mistake so I'm inclined to leave it at that.