Why do hard drives fail
At the core, hard drives are mechanical assemblies, which like all other mechanical assemblies, are destined to suffer from misalignment flaws in the long run. The hard drive is said to have crashed when the data that resides in it can’t be accessed on a normally configured terminal. Uncontrollable environmental factors come into play to cause hard disk crashes, thus, making it an inevitable and commonplace occurrence.
A hard disk might tolerate severe jerks at some times, but then, there will be moments when a slight impact would suffice in inflicting severe damage. The design and architecture of a hard disk is very intricate, and it is pretty difficult to understand it completely for a layman. For the time being, it is worth knowing that the read and write head of a hard disk is mere nanometers away from magnetic data storage plate. This makes a collision of the head and the storage platter a highly probable risk. Collision might just be a misleading term in such a case. Even a slight brushing is enough to result in a ‘hard disk crash.’ Data damaged in this crash is very hard to recover, and this can be done by trained professionals with specialized equipment. Also, the failure of the pressure and temperature equalizers inside the hard disk may render the device an easy prey to crash causing agents. A minute dust particle also qualifies as an infiltrator when inside the hard disk assembly. It may get jammed between the read write head and the storage surface, thus creating a vicious cycle of formation of bad sectors in the disk. It barely takes moments to completely stun the disk when this happens. The electronic regulators inside the hard disk can malfunction and render the device useless.
Hard drive manufacturers realize the uncertainty with hard disk functioning, and in order to provide the customers with reliable estimates of the age of the device, conduct tests and experiments on the drive before commercial release. The manual might mention the ‘Mean Time Between Failures’. However, it does not include the risks posed by environmental factors, and hence, isn’t an efficient indication of the disk’s life. It is generally observed that an immaculately designed hard disk performs pretty nicely for the expected life time, provided that external factors are controlled. Manufacturing glitches, in most cases, exhibit themselves in the form of hard disk malfunctioning in mere months from the date of purchase.