The hard drive in your computer is only one of several mechanical parts, and over time these parts can wear out. Many factors contribute to the life expectancy of your hard drive including: heat, shock, and usage so individual results will vary, but just how long do them last?
Most hard drive manufactures offer warranties ranging from 1 to 5 years. The longer the manufacturer’s warranty, usual, is related to build quality and price. As with all electronics sometimes they just fail.
BackBlaze released the findings 4 years into a 6 year study on 25,000 consumer grade hard drives it installed in their data center. These drives were from various manufactures. After 18 months 5.1% of the drives had failed, between 18 months and 3 years only an additional 1.4% of the drives had failed. The study was recently updated and can be found here.
So after 3 years of usage 6.5% of the hard drives they started with had failed.
After 3 years things get much worse. Between years 3 and 4 and additional 11.8% of the initial drives failed bringing the total failure rate to 18.3% or roughly 1/5 (5000 drives) the initial 25,000 drives. BackBlaze goes on to estimate at 6 years you would have a 50/50 chance of hard drive failure.
If you keep current and up to date backups of your systems, hard drive failures tend to be nothing more than an inconvenience that is usually rectified by purchasing and new drive, installing your software, and restoring your system backups. If you do not backup your systems hard drive failures result in a loss your computer data.
Replacing your current hard drive is a very simple process of purchasing a new hard drive and imaging your old drive to your new drive. Typically this can be done in 20 to 60 minutes depending on how much data is stored on the drive.
I personally replace my systems hard drives at around the 3 year mark and install reinstall windows instead of imaging. This usually takes longer and personal settings need to be re-setup but system performance is usually increased in the long run.
With new hard drive costing as little as $50-$60 dollars, replacing them every 3-4 years offers peace of mind without hurting the budget.