All the pieces I turn get labeled as factory seconds because I find a flaw in all of them. Most are not obvious to those looking at the project. My neighbor gets a bit miffed when I point them out. Of course the flaws are what sets most pieces apart from assembly line stuff that comes out exactly like the one in front of it. So in a word flaw means character I guess. When I bought my Gibson 335 years ago it was listed as a factory second and the salesman offered to give me the guitar if I could find the flaw. I inspected that guitar for an hour because the offer of a free guitar was too good to pass up. I finally gave up and the salesman showed me some figure in the wood that was errant – I thought that was done purposely for character!