Originally Posted by alanbikehouston
It is my understanding that this rotating plate design is intended to make the locks more difficult to pick. New OnGuard and Kryptonite locks have a red sticker on them warning owners to fully seat their keys before turning the key. If you remember to do that, things will go smoothly.
Disk locks generally have two advantages over "normal" pin and tumbler locks - they require different tools to pick (which are very expensive) and the top disk rotates freely meaning that drilling the lock is almost impossible.
I have also heard that ABUS has a new type of disk lock that can't be picked with the tools used for disk locks, as the disks won't turn unless the key is all the way in the lock (except for the first disk to make it drill-resistant). This would also prevent the disks from becoming misaligned.