At some point, pieces wear out and you get rid of them. Usually it's because of fraying or breakdown of the lace, or the hair getting too thin because of shedding. You could always get hair added to a thinning piece, and maybe some people still do, but costs have come down so much with Toplace, etc. that it's almost not worth it anymore. How long they last is different for everyone.

To answer your question, pics of an aging piece should be the same as any other pics--- because if the piece is so bad that you would notice a problem in a pic, you shouldn't be wearing that piece anymore.....