Although it is easy to believe that SSDs' lack of moving parts should make them more reliable, these results are not surprising:
- Experience shows that vendors tend to exaggerate the reliability of their products.
- Root-cause analysis of failures in hard-drive systems shows that 45-75% of failures are not due to the disks themselves, so that even if SSDs were a lot more reliable that hard drives but were used in similar systems, the effect on overall system reliability would be small. In fact, most of the SSDs surveyed were used in hybrid systems alongside disks.
- The flash SSDs have even more software embedded in them than disk drives. Thus even if their raw storage of bits was more reliable than the disk platters, they would be more vulnerable to software errors.
The only definitive conclusion we can reach right now is that you should take any claim of reliability from an SSD vendor with a grain of salt.