On Thu, 14 Jan 2016 22:01:18 +0800, Mr. Man-wai Chang wrote:

Modern hard disks are very very reliable!

No. Not really. Not all of them. It depends on the HDD manufacturing. Some
models are durable, and some are not.

My 160GB WD only lasted about a year while my 3 years old 40GB Seagate is
still fine.

FYI, my environment is somewhat harsh. No air conditioning (because it's in
an open room), and the air is not clean enough.