my 360 only hurt the first game I ever bought thats cause while on somehow I decided it was a good idea to turn the console vertical while game was still inside spinning around...
I took game back to the store the following day and said somehow my 360 scratched it and got a new replacement... *cough*
hmm come to think of it also had a problem with Mass Effect and Fable II discs.. they both became unreadable... when I took out both discs they had a ring line (of about 4 mm wide) going around the disc which I thought the 360 had permanently caused but I was able to firmly rub it off and they worked again.
So I know the main causes for me are either moving the 360 while disc is spinning or the lens mechanism parts are touching the 360 because of certain games that are data intensive but they are not scratches its smudge marks..
also living near a train line or motorway probably doesn't help much if you house vibrates...
but anyway I dont have any disc problems now since games are installed to the HDD...
