A small USB drive may seem like a suitable place to keep files for years, especially because it is easy to transport and inexpensive to use. However, relying on it as the only copy of data exposes files to loss, damage, or gradual corruption. Therefore, old drives warrant an urgent review and the creation of backups.
Risks Beyond Loss or Physical Damage
The small size makes USB drives easy to lose or destroy, whether they are left somewhere or dropped while being transported. Even if the drive remains safely stored, flash memory has a limited lifespan linked to the number of write cycles, which the source generally estimates at between 10,000 and 100,000 cycles for portable storage. This is not a major problem when the drive is used for archiving without frequent modifications, but it becomes significant when files are copied to it daily or weekly.
USB drives also generally do not provide the TRIM capabilities available in conventional SSDs to recover part of the usable space. A phenomenon known as bit rot may also occur, in which memory cells lose their electrical charge over time, potentially flipping some bits and corrupting data. The source also states that cosmic rays can flip bits, with a low probability estimated at approximately once per gigabyte per month at sea level.
In addition, the points of failure are not limited to the memory cells; the connector and controller chips may fail because of shocks, corrosion, or poor manufacturing. Storing the drive in an extremely humid environment may also lead to mold contamination.
What Does the 3-2-1 Rule Mean in Practice?
For important data, the practice known as the 3-2-1 rule recommends keeping at least three copies: two local copies on two storage media, and one copy uploaded to a cloud service. The plan can be strengthened by keeping one of the copies at a different address or inside a fire-resistant safe, although that may be excessive for ordinary files.
Using cloud storage does not mean eliminating local backups. Subscriptions may require ongoing fees, the internet connection may be interrupted, and large data centers are not immune to catastrophic failures. Multiple media therefore reduce reliance on a single point of failure or a single provider.
When Should Files Be Moved Away from a USB Drive?
If the files are genuinely important, it is best to copy them to an external SSD or cloud storage, while keeping an additional local copy according to the importance of the data. Less sensitive files can be stored on the computer's internal storage, but recovering them may become complicated if the device fails and the user has to remove the drive and connect it to another computer.
Editorial reading from certi.news: The problem is not that every USB drive will suddenly stop working, but that its design does not guarantee that the only copy of data will remain intact for many years. The practical value here is to turn the old drive from a “final archive” into a source for multiple copies, while recognizing that the source does not specify a uniform service life for all drives or provide a practical condition test. This makes reviewing and transferring important files a precautionary decision, not one tied to a fixed technical schedule.