How do stored DVDs get scratched?
 

I have a lot of DVDs that I've made stored in spindles. However, I've noticed that many of them are scratched on the bottom of the discs. I'm confused about how this could happen, since they've only been stored on spindles?

Is there a way to fix that & does it effect how the DVD plays?

Discs on spindle can rotate relative to each other, and may do so if the pack is moved or rotated.. Any tiny dust or grit between the discs, (e.g., on the top if the disc underneath) can induce a scratch if the discs move relative to each other. Handling discs can leave skin oils on the disk surface (including the top of a lower disk) that will attract dust/dirt/grit to make matters worse. Similarly inks that are not fully dry can pickup dirt. Discs are plastic adn might unde 5the right circumstances develop a static charge and attract dirt.

The risk is higher with printed labels and discs that do not have raised hub rings.

If the scratches exceed the error correction capability of the player you will hear/see skips, glitches in the playback. (I find it happens often with recorded books on disc from the local library.) In bad cases the disc maybe unplayable.

Minimize the likelihood by buying high quality discs, handle them with care, and store in individual library cases (not on spindles). If the material is important - keep a backup that you do not play.

Get cases, store vertically, no scratches

Spindles work great, but only if not disturbed too much.
Be careful about case -- some warp a disc, and that can be really bad too!

how about paper sleeves? should they give good enough protection when put together in a box?