However - I don't see a whole-lota difference in saying corrupt vs wearing-out.

''Wear leveling allows data writes to be evenly distributed over the storage media. More precisely, wear leveling is an algorithm by which the controller in the storage device re-maps logical block addresses to different physical block addresses in the solid-state memory array. The frequency of this re-map, the algorithm to find the "least worn" area to which to write and any data swapping capabilities are generally considered proprietary intellectual property of the controller vendor.
Figure 2 (below) shows a normalized distribution of writes to a flash card that does not use wear leveling. In this instance, the data gets written to the same physical block. Once that physical block wears out and all spare blocks are exhausted, the device ceases to operate, even though only a small percentage of the card was used''

http://www.storagesearch.com/siliconsys-art1.html

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