The fact is, even it wouldn't matter as-is if the data took 10000 years to degrade from the platter itself. Most consumer hard drives those days are made for la

The fact is, even it wouldn't matter as-is if the data took 10000 years to degrade from the platter itself. Most consumer hard drives those days are made for laptops, which are probably used for less than 5 years on average. Even if you consider external HDs and desktop HDs, a long of a lifetime isn't much use: the control electronics themselves fail fast, and the mechanical reliability even faster. It's an optimization rule of thumb: in an optimal trade-off for (e.g.) maximum reliability for cost, the reliability of each element will tend to be close (actually the derivative of the reliability vs cost will be equal, but this tends to imply the former) -- i.e. you improve the least reliable and sacrifice the most reliable, even if the most has very reliability.