How Do Hard Drives Fail?

hard drive

Everybody with a computer uses a hard drive and there are tens of thousands of choices available for people who are looking to safely store their information on these little pieces of tech. Unfortunately, though, failures happen – instances that can lead to the loss of precious business or personal data. But how do such major issues happen?

How Common is Hard Drive Failure?

A company called Backblaze analyses the failure rates of 73,653 hard drives every year. In some, they recorded no failures, but in others, such as the WDC-sold hard drives, the failure rate was a massive 3.88%. That means there’s a tremendous variance in the frequency of hard drive failures – with some (like the ST1500DL003) having incredible failure rates of 90.2%.

These rates don’t accurately reflect the average consumer experience as they were drives used in datacenters, but hard drive failures can have dramatic effects on the lives of everyday people. 24×7 IT Solutions documents a health products company who were unfortunate enough to have 2 hard drives fail on them at once, costing them $40,000 and 9 days of no computer network!

Mechanical Failure

Hard drives are the hardware that is governed by the laws of mechanics. This means that wear and tear or hard impact can cause mechanical issues in areas like the read/write head or motors. This is especially likely with older disks and when a mechanical failure has occurred, the hard drive will either not boot up at all, make weird noises (a sure-fire sign you need to back-up fast) or freeze and crash regularly. Much mechanical damage is irreversible so backing up regularly is the best way to prevent against this.

Electrical Failure

Electrical failure is terrifying because it can happen when there’s a surge of power voltage (something you won’t be able to control). If you’re using your desktop computer and a lightning strike or a power line is being damaged, the electronic circuitry can be damaged, and you might not be able to recover your data.

System Failure aka Logical Failure

Your hard drive can fail not due to any physical issue, but instead due to data being corrupt or even from viruses and malware. This works by prohibiting the logical pathways that your computer needs to function correctly – whether that’s being able to access data or just starting up. Even something as simple as deleting system 32 can lead to a logical failure that stops you from being able to use your computer.

Bad Sectors

Hard drives work by reading magnetic data. Magnetism, however, is not failproof and if the magnetic alignment is damaged, leading to misalignment, the whole rotating platter that your hard drive needs to work will become impossible to access. A bad sector is an area of data that’s damaged due to this misalignment, but it can also happen in solid-state drives too just from natural ware. When bad sectors get bigger, memory capacity will decrease, and data corruption can occur, leading to a logical failure. If your computer is frequently lagging, showing some files as inaccessible or giving you CRC errors, your bad sectors might be getting out of control.