Why does a hard disk drive (HDD) tend to be more prone to failure?

A hard disk drive (HDD) is more prone to failure primarily because it contains a lot of moving parts. The fundamental design of an HDD includes spinning disks (platters) and read/write heads that are mechanically moved to access data. This reliance on mechanical movement increases the risk of physical wear and tear, as well as susceptibility to disturbances like shocks or vibrations that can misalign the read/write heads or damage the platters.

In contrast, solid-state drives (SSD) utilize flash memory with no moving parts, significantly reducing the risk of mechanical failure. Operating at higher energy levels or using optical technology does not inherently affect the durability of HDDs in the same way that their mechanical nature does. The presence of moving components is the critical factor that leads to a greater likelihood of failure in HDDs, distinguishing them from solid-state alternatives.