It happens accidentally.  Consider the following -- over a 5 year ownership of a console, an average owner has at least 50% a chance of moving or bumping or their 360 somehow falling over while operating.  This is my own estimate, but it probably isn't far from the mark.  Microsoft's internal (private) numbers would almost certainly agree.

This would cost the average Xbox 360 owner at least $20.  Because they're more likely to be using a new $60 game than an old game only worth $20 and if this happens to 1/2 of all owners, let's cut the price in half.

Microsoft said they didn't put foam bumpers in the DVD drives because it would have increased the cost of the xbox 360 by 50 cents.  So they'd rather see you lose $20 .00than spend $0.50 fixing their own problem.

Also, consider that they knew the system was shipping with hardware problems, the RROD issue in particular, when they decided to ship it defective.

+1

I've scratched my Halo disc... I couldn't play 3 of the multiplayer maps

havent scratched a disk yet.

Not to bring the PS3 into this but... This is the main reason I wish all my JRPGs were on the PS3. I buy, and sell, a LOT of RPGs (used and new), and I hate it when they are scratched. I take super good care of my discs, and when my own console scratches one, I feel pretty upset.

If the X360 didn't scratch discs, I would be utterly satisfied with it (since I got a new Jasper recently, to replace my RRoD Xenon, and sold the refurb instead). As is, I don't like getting RPGs on the 360 for that reason alone... okay and because the D-pad is too sensitive on the 360 for my (apparently two-left-thumbed) RPG needs.

I really wish MS would address this important need.

My 360 runs over 13 months vertically and none of my discs have any scratches.

I've got a Hitachi-LG drive

I didn't cuz I knew better, but I've done it so many times with my PS3 that I've lost count.  And I do it in front of my 360 fanboy friends who have scratched 360 discs just to show off=P

By the way, if you have a Hollywood Video rental store near you, they offer a disc repair service for FREE - my friend took his Rainbow Six: Vegas Xbox 360 disc that suffered this very fate up there, and when they finished you could barely see the damage, and the disc was readable again (enough so that he could install it and just use the disc to start the game.  I highly reccomend their disc repair service if you have one in your area and have had this problem and possibly still have the game disc.  

Yeah well this is old news. But it can be avoided if people arnt retarted. Its amazing that some people have as little common sense as they do. Who reorients their xbox while playing. And the other question is Why. i mean cmon people